Blue Hue around images....?

[JDP]

Hello,

This is an amature/school boy error. I have a group of sparrows [i think] living in my neighbors gutter and i try and get attempt a remotely decent image but when there is one i like it is damaged by a blue hue around the image...

Is this the time i require a UV filter?

This is what i mean....

F/5.6, 1/1000, ISO400

Thanks in advance for help..

 

[trencheel303]

No UV filter required... that's just very bad Chromatic Abberation presumably from a bad lens, the light contrast not helping either and it looks as if you've heavily cropped it.

Any contrast of light like that where the sky has completely blown will show CA on even the most expensive of lenses.

 

[eccles]

Purple fringing is caused in high contrast situations by interaction between the lens coatings and your sensor. It is usually present on cheaper and/or older lenses and affects some camera sensors more than others. A better lens or more care in shooting to avoid this type of lighting is your only answer. A UV filter won't help.
It is also possible that the lens is back focussing slightly which can give a similar effect caused by longitudinal CA. You might want to check your autofocus accuracy.

 

[JDP]

No UV filter required... that's just very bad Chromatic Abberation presumably from a bad lens, the light contrast not helping either and it looks as if you've heavily cropped it.

Any contrast of light like that where the sky has completely blown will show CA on even the most expensive of lenses.

Okay, thank you. I am using a Tamron 70-300mm... yeah i did do quite a big crop.

How would i be able to avoid this issue?

Purple fringing is caused in high contrast situations by interaction between the lens coatings and your sensor. It is usually present on cheaper and/or older lenses and affects some camera sensors more than others. A better lens or more care in shooting to avoid this type of lighting is your only answer. A UV filter won't help.
It is also possible that the lens is back focussing slightly which can give a similar effect caused by longitudinal CA. You might want to check your autofocus accuracy.

Thanks for the detailed information. It's a cheap lens, £123. How will i be able to avoid this, (more like my careless shooting is the issue).

Oh okay, how do i check the autofocus accuracy?


Thanks again both of you.

 

[HoppyUK]

Okay, thank you. I am using a Tamron 70-300mm... yeah i did do quite a big crop.

How would i be able to avoid this issue?



Thanks for the detailed information. It's a cheap lens, £123. How will i be able to avoid this, (more like my careless shooting is the issue).

Oh okay, how do i check the autofocus accuracy?


Thanks again both of you.

Don't shoot a shaded subject against a very bright background like that, and don't crop - fill the frame. That's hard I know, but just doing those two things would transform the result.

Get a better quality lens. That's asking a lot from a cheap consumer zoom there.

 

[JDP]

Don't shoot a shaded subject against a very bright background like that, and don't crop - fill the frame. That's hard I know, but just doing those two things would transform the result.

Get a better quality lens. That's asking a lot from a cheap consumer zoom there.

Okay, thanks for the advice. Ill try get into a better possiton!. Okay, will do. Ill give it ago.

Really? That would probly explain why some other images i take are either, OOF, soft , or it looks like there is some sort of coating on the image. :thumbsdown:

can you recomend any lenses which would be best for animal/wildlife?

would the Canon EF 70-200mm f/4.0 L USM Lens be sufficant...?

Thanks again.

 

[HoppyUK]

Okay, thanks for the advice. Ill try get into a better possiton!. Okay, will do. Ill give it ago.

Really? That would probly explain why some other images i take are either, OOF, soft , or it looks like there is some sort of coating on the image. :thumbsdown:

can you recomend any lenses which would be best for animal/wildlife?

would the Canon EF 70-200mm f/4.0 L USM Lens be sufficant...?

Thanks again.

Looking at it in the round, with that sparra you've got subject issues, technique problems, and also equipment shortcomings.

Subject - get close, get some sun on the subject, avoid bright backgrounds.

Technique - nail focus, practise, that's not the lens/camera. Don't crop. Keep the shutter speed up.

Equipment - quality long lenses are very expensive. 70-200L is good, but maybe not long enough, IS version costly. Canon 70-300 IS would be a leg up, but like most consumer zooms it's weakest at 300mm. If you're serious about this sort of thing, Canon 100-400L is the one most people end up with - £900 used?

 

[JDP]

Looking at it in the round, with that sparra you've got subject issues, technique problems, and also equipment shortcomings.

Subject - get close, get some sun on the subject, avoid bright backgrounds.

Technique - nail focus, practise, that's not the lens/camera. Don't crop. Keep the shutter speed up.

Equipment - quality long lenses are very expensive. 70-200L is good, but maybe not long enough, IS version costly. Canon 70-300 IS would be a leg up, but like most consumer zooms it's weakest at 300mm. If you're serious about this sort of thing, Canon 100-400L is the one most people end up with - £900 used?

Okay, thanks will do. It's from my bedroom window, so ill climb onto the flat roof and see what i can get. Will do. Okay, i have just finished college, so i have a long 7/8 week holiday so i can practise. Wont crop, how come tight crops are so much of an issue? do you lose some of the subject? Will keep the shutter speed up.

Really, okay fair enough.. being a student about to attend uni, money is tight so i don't think I'd be able to get a decent lens for a while. I'm very serious about wildlife and photography (I'm serious enough, I'm doing Wildlife Conservation at uni).. I will have a look into that lens. That's not too bad, ill have a look on some websites.

Thank you!

 

[HoppyUK]

Okay, thanks will do. It's from my bedroom window, so ill climb onto the flat roof and see what i can get. Will do. Okay, i have just finished college, so i have a long 7/8 week holiday so i can practise. Wont crop, how come tight crops are so much of an issue? do you lose some of the subject? Will keep the shutter speed up.

Really, okay fair enough.. being a student about to attend uni, money is tight so i don't think I'd be able to get a decent lens for a while. I'm very serious about wildlife and photography (I'm serious enough, I'm doing Wildlife Conservation at uni).. I will have a look into that lens. That's not too bad, ill have a look on some websites.

Thank you!

Good! Give it a go. And don't throw money at it just yet - that's not the main problem.

Wildlife is very hard, and birding is the hardest of them all as they're generally small. The guys who do it best are very skilled photographers, have great field craft, endless patience, and big expensive lenses.

To see what your lens and camera are capable of, set the zoom on max and point it at something small. Like a cup or mug, in good light. That's the kind of size subject you're looking at. Shoot at f/8 or f/11 to get the best out of that lens and the highest shutter speed you can. Bump the ISO to get that. Fill the frame. You'll be much closer than you think! But you'll be pleasantly surprised at the quality you get compared to the pic you posted.

Cropping is death to image quality. There are a number of reasons why, and it's not just about pixels. It's about the size of the image on the sensor so fill the frame and use every square mm of sensor area you can.

In the end, you always end up with a compromise of all the various factors. The skill is in choosing the best set under the circumstances.

 

[Richard King]

Purple fringing is caused in high contrast situations by interaction between the lens coatings and your sensor. It is usually present on cheaper and/or older lenses and affects some camera sensors more than others. A better lens or more care in shooting to avoid this type of lighting is your only answer. A UV filter won't help.
It is also possible that the lens is back focussing slightly which can give a similar effect caused by longitudinal CA. You might want to check your autofocus accuracy.

Wrong

Chromatic abberation is not caused by the anti reflective coating, and is most generally caused by TCA, which is caused by:


- use of non best form lenses
- using lens materials with a poor ABBE value: http://en.wikipedia.org/wiki/Abbe_number - essentially you want a meaterial that bends the red and blue ends of the spectrum the same amount. This never happens, however, if there is a big varience, then you get chroamatic abberation http://wiki.panotools.org/Chromatic_aberration. This page also expalins LCA, which isnt evident in the image. This page also expalins sensor bloom
- not using techniques like cleverly pairing lenses with different and opposing chromatic abberations (as used in a APO or apochromatic lenses - see http://www.achromaticlens.com/)

Anti reflective coatings have a residual hue, which is why your lenses may have a green / purple / yelow or blueish reflection. This has nothing to do with sensor bloom, or chroamtic aberations


The main issues with the image is
1. a poor quality lens used
2. a very high contrast background to the subject
3. attempting to PP or expose for the subject, made the issue stand out more (assumtion is no flash was used)
4. heavy crop essentially magnifies the issue (or makes what is there show more)

Shooting against a darker background would be the obvious option here in terms of reducing the edge contrast

learning the lens limits wil help, but ultimatally, if you want to shoot birds against a white sky, you need better glass

The proiblem with things like birds, is, you cant really use flash, you cant really whip a reflector in. this leaves changing the shooting position to ensure the background is more sympathetic

 

[JDP]

Good! Give it a go. And don't throw money at it just yet - that's not the main problem.

Wildlife is very hard, and birding is the hardest of them all as they're generally small. The guys who do it best are very skilled photographers, have great field craft, endless patience, and big expensive lenses.

To see what your lens and camera are capable of, set the zoom on max and point it at something small. Like a cup or mug, in good light. That's the kind of size subject you're looking at. Shoot at f/8 or f/11 to get the best out of that lens and the highest shutter speed you can. Bump the ISO to get that. Fill the frame. You'll be much closer than you think! But you'll be pleasantly surprised at the quality you get compared to the pic you posted.

Cropping is death to image quality. There are a number of reasons why, and it's not just about pixels. It's about the size of the image on the sensor so fill the frame and use every square mm of sensor area you can.

In the end, you always end up with a compromise of all the various factors. The skill is in choosing the best set under the circumstances.

Will do. Okay, ill wait a bit longer.

Ohkay, yeah i understand that. They are brilliantly skilled. Hopefully in about 3/4 years after my degree ill have the good field craft. I want to specialise in Biodiversity surveying so ill need endless patience too. And i assume lots of knowledge on the land they are on so they know what animals/plants to look out for. That'd be why their pictures are to die for. One day ill be able to afford something proper decent.

Okay thanks for that ill give that ago in a minuet . Its just simple techniques like this which brings out the best in the lenses i guess, even if they are cheap.

Ah i see, thanks for that. The skill comes along with a lot of trial and error, as each pic is different?

Thank you again so much, this help is really appreciated.

 

[Richard King]

Nothing wrong with a cheap lens. Lean how to use it, learn its limits, push it, swear at it. Ultimatally, if you learn how to get decent results out of it, when you do get a good lens, your will be skilled enough to push that too

 

[RevOnline]

Nothing wrong with a cheap lens. Lean how to use it, learn its limits, push it, swear at it.

This is pretty true in the case of this lens - in good light with a well thought out picture it can be pretty good. Or at least good enough.

In this case - think more about the sparrows than the lens. With patience (lots of patience) and a few breadcrumbs (or similar) you should be able to wait for them to come to you, rather than impulsive snaps. Get some food put down in a specific, easy to photograph place every single day for the next few days - then one day put the food down as normal but have your camera sat on a tripod pointing at it. You'll get a good picture sooner or later.

 

[JDP]

Wrong

Chromatic abberation is not caused by the anti reflective coating, and is most generally caused by TCA, which is caused by:


- use of non best form lenses
- using lens materials with a poor ABBE value: http://en.wikipedia.org/wiki/Abbe_number - essentially you want a meaterial that bends the red and blue ends of the spectrum the same amount. This never happens, however, if there is a big varience, then you get chroamatic abberation http://wiki.panotools.org/Chromatic_aberration. This page also expalins LCA, which isnt evident in the image. This page also expalins sensor bloom
- not using techniques like cleverly pairing lenses with different and opposing chromatic abberations (as used in a APO or apochromatic lenses - see http://www.achromaticlens.com/)

Anti reflective coatings have a residual hue, which is why your lenses may have a green / purple / yelow or blueish reflection. This has nothing to do with sensor bloom, or chroamtic aberations


The main issues with the image is
1. a poor quality lens used
2. a very high contrast background to the subject
3. attempting to PP or expose for the subject, made the issue stand out more (assumtion is no flash was used)
4. heavy crop essentially magnifies the issue (or makes what is there show more)

Shooting against a darker background would be the obvious option here in terms of reducing the edge contrast

learning the lens limits wil help, but ultimatally, if you want to shoot birds against a white sky, you need better glass

The proiblem with things like birds, is, you cant really use flash, you cant really whip a reflector in. this leaves changing the shooting position to ensure the background is more sympathetic

Sorry i didn't reply, i miss your post. - Thank you for the detailed information, i am going to do a lot of reading on how to find the lens limits. When you say 'better glass' i assume you mean a better lens?

Yeah that's very true about birds. Though, im lucky enough to be able to practice on captive birds alot at college (i work with lots of small birds)
Yeah true, it's hard with these sparrows because they are in a neighbors gutter and you can only see them at one position, my bedroom window and they don't usually approach the tiles on the roof. So that gets ruled out. I am going into Brighton to try some techniques and i will try find the limit of my lens.

Nothing wrong with a cheap lens. Lean how to use it, learn its limits, push it, swear at it. Ultimatally, if you learn how to get decent results out of it, when you do get a good lens, your will be skilled enough to push that too

Okay cool, i shall. I like to swear so its all good, lol. Is there anywhere i could get information on how i can use it to the limits and finding the correct techniques -runs to browse forums-. Thanks also for the reassurance, i havent wasted my money on the cheap lens.

Thanks again mate!

 

[JDP]

This is pretty true in the case of this lens - in good light with a well thought out picture it can be pretty good. Or at least good enough.

In this case - think more about the sparrows than the lens. With patience (lots of patience) and a few breadcrumbs (or similar) you should be able to wait for them to come to you, rather than impulsive snaps. Get some food put down in a specific, easy to photograph place every single day for the next few days - then one day put the food down as normal but have your camera sat on a tripod pointing at it. You'll get a good picture sooner or later.

Okay thanks mate, ill give that ago! thats a brilliant idea. I just wont tell my perants. .

I just found a bird feeder in my guarden. I have set up my Tripod and camera with the lens ready to shoot when its all sorted. im going to try and sort out a better background for it.. Might even move the camerea into my concervetory when i can get much closer (but there will be glass in the way! . Ill have a play with things.. see what i can get.

 

[Undercrank]

James,

Lens elitism can undermine an amateur shooter's confidence and the prohibitive cost of better or pro lenses is a step too far for many. Away from gearhead hype and misinformation there's a lot of potential in less expensive lenses on DSLRs.

Happily software will usually help too by dedicated routines or, in this case, just targeting blue and magenta tones. You can pick them out precisely, or sometimes just adjust the entire image, as in this case.

 

[HoppyUK]

James,

Lens elitism can undermine an amateur shooter's confidence and the prohibitive cost of better or pro lenses is a step too far for many. Away from gearhead hype and misinformation there's a lot of potential in less expensive lenses on DSLRs.

Happily software will usually help too by dedicated routines or, in this case, just targeting blue and magenta tones. You can pick them out precisely, or sometimes just adjust the entire image, as in this case.

I don't think there has been much lens elitism on this thread.

With respect to you Sam, speaking of misinformation, the idea that you can post process your way out of fundamental image problems is very misleading.

 

[RevOnline]

With respect to you Sam, speaking of misinformation, the idea that you can post process your way out of fundamental image problems is very misleading.

I have to agree with this - as I have already stated in the thread the lens can produce totally acceptable images given the right circumstances. Being clever about how you use it will not only create much better pictures, it'll almost certainly make you a much better photographer too.

 

[JDP]

James,

Lens elitism can undermine an amateur shooter's confidence and the prohibitive cost of better or pro lenses is a step too far for many. Away from gearhead hype and misinformation there's a lot of potential in less expensive lenses on DSLRs.

Happily software will usually help too by dedicated routines or, in this case, just targeting blue and magenta tones. You can pick them out precisely, or sometimes just adjust the entire image, as in this case.

Cheers mate, i was the one who brought up the expensive lens, But i guess i need to deal with a cheaper lens practise, means i will be better for when i can get a lovely expensive one.

Awesome, i like how the picture has come out...! i didn't relise, thanks ill give that ago. Really i want to get good camera/lens skills and build up the skills required for when im ready to go out in the real world and start shooting & trying to become an LRPS!

I don't think there has been much lens elitism on this thread.

With respect to you Sam, speaking of misinformation, the idea that you can post process your way out of fundamental image problems is very misleading.

I'm not a real big fan of post processing, apart from the basic stuff anyway, such as the sharpening, and what you can do in RAW.

I have to agree with this - as I have already stated in the thread the lens can produce totally acceptable images given the right circumstances. Being clever about how you use it will not only create much better pictures, it'll almost certainly make you a much better photographer too.

Indeed. i have taken some pictures, using one of the techniques on the page, adapted it a little and took a picture of my cat and its unbelievable how much better the picture has become! (with a lot less photoshop work too!)

 

[Undercrank]

Er, for what it's worth, (and with respect to you Richard), I wasn't actually referring to the contents of this thread but had in mind the wider online world in general where, unfortunately, misinformation isn't that hard to find. Sorry I didn't make that clear, though on reflection I'm not sure I needed to!

Nor was I daft enough to suggest we can post process our way "out of fundamental image problems". Would be a very long post getting into the balance of all that, though I've had a crack at it elsewhere.

Finally, in our main context of glass shortcomings (and if the truth be told, any cause of fringing), after a lot of personal processing experience it's true that "software will usually help".

So James, it's useful to keep that in mind too. It's not that tricky really and can be very effective.

Best regards,

Sam

 

[HoppyUK]

Er, for what it's worth, (and with respect to you Richard), I wasn't actually referring to the contents of this thread but had in mind the wider online world in general where, unfortunately, misinformation isn't that hard to find. Sorry I didn't make that clear, though on reflection I'm not sure I needed to!

Nor was I daft enough to suggest we can post process our way "out of fundamental image problems". Would be a very long post getting into the balance of all that, though I've had a crack at it elsewhere.

Finally, in our main context of glass shortcomings (and if the truth be told, any cause of fringing), after a lot of personal processing experience it's true that "software will usually help".

So James, it's useful to keep that in mind too. It's not that tricky really and can be very effective.

Best regards,

Sam

Thanks for that clarification Sam And welcome to TP, which I should have said earlier

I agree that there is a lot of crap around the web, especially from equipment snobs, and general nonsense that you can't take a decent image without an an L lens at least. But one of the reasons I hang around here is that it's a pretty down to earth place, and refreshingly free of bickering Americans who like to throw money at everything and pixel peep their pictures of walls and things.

In fact, while I was writing my comment above, I was thinking about what you can actually do with software to address "fundamental image problems" even if I don't think they apply in this case.

Things like distortion, CA and vignetting are now commonly treated in-camera with software, rather than optically, and I'm a big fan of that approach and the various benefits that come with it.

 

[trencheel303]

and refreshingly free of bickering Americans who like to throw money at everything and pixel peep their pictures of walls and things..

How rather racist!

 

[HoppyUK]

How rather racist!

Then to even it up a bit, I'll say that there are a few bickering Brits on here as well. Mentioning no names...