Cropping Confusion.

sk66 said:
Like I said earlier, you're getting into the circle of equivalence... if you use a shorter FL it has to be sharper in order to generate the same results. That's because it is going to project the image smaller onto the sensor, which requires it be resolved by a smaller area/pixels, and it's going to be cropped harder/enlarged more.

I see a couple of possible benefits to using the other lenses. One is that they are faster which means more light. The second is that they are not as critical of technique (camera shake). But again, the images will be cropped/magnified more which tends to equalize things.
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Thanks Steven. I was actually in my hide when I read that, I had a good session and stuck with the Sigma. I'm home now and going through the images, watch this space.
 
Again, for reference but I'm happier. Much closer this time too, so less of a crop, within 12 feet now and it was also skipping about on my fabric pop up hide, inches above my head.

The best of the light was gone for this, it was much better earlier, maybe even too good as I struggled with the whites on my other image posted earlier today.

5Div, Sigma 150-600C, 600mm, f6.3, iso 1250, 1/1000sec.

This one has had too many sticklebacks me thinks. ;)

IMGL4363 DPP LR CS6 JP.jpg
 
nandbytes said:
I imagine your sigma 150-600mm will still be better than any 100-400mm or 400mm/5.6 cropped down to match it.

Assuming you are using 5D4 which is 30MP:
Cropping down a result from a 100-400mm or 400mm/5.6 will result in 13MP i.e. 1.5x crop.
Cropping down from a 300mm lens will result in 7.5MP i.e. 2x crop
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That assumes that the lenses can resolve at least as fine as the sensor's pixel pitch; and they probably can't. For example, the **Tamron 150-600 can only resolve about 10 MP on the 5D IV at 600mm (@f/8). Whereas the 100-400 reaches 14MP at 400mm and the 300/4 achieves 18MP.

Anything above 12MP actually resolved/remaining is very good; below ~8MP it starts to become readily apparent.

(**I couldn't find test data for the Sigma on the 5D IV, but it probably won't be hugely different)
 
Dale. said:
Again, for reference but I'm happier. Much closer this time too, so less of a crop, within 12 feet now
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Man, try the other lenses... you should be getting much better results at that distance.
Even though it's wide open and would be sharper stopped down a bit, I don't really see anything wrong w/ the settings. So either it's technique, or the lens is misfocusing.

Edit: how far "within" 12ft? The lens has a MFD of ~ 9ft.
 
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sk66 said:
Man, try the other lenses... you should be getting much better results at that distance.
Even though it's wide open and would be sharper stopped down a bit, I don't really see anything wrong w/ the settings. So either it's technique, or the lens is misfocusing.
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I don't think the upload has helped, even the text is a little mushy.

I will definately try the other lenses though, whilst I save for the 600L. ;)
 
sk66 said:
That assumes that the lenses can resolve at least as fine as the sensor's pixel pitch; and they probably can't. For example, the **Tamron 150-600 can only resolve about 10 MP on the 5D IV at 600mm (@f/8). Whereas the 100-400 reaches 14MP at 400mm and the 300/4 achieves 18MP.

Anything above 12MP actually resolved/remaining is very good; below ~8MP it starts to become readily apparent.

(**I couldn't find test data for the Sigma on the 5D IV, but it probably won't be hugely different)
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sigma is definitely better than the original tamron. The G2 version is supposedly improved upon the G1.

Besides those scores which I assume you got from dxomark(?) should be take with a large grain of salt. There are many inconsistencies.
 
sk66 said:
Ok.
Just for reference, these are the kind of results I can get pretty easily with the Sigma 60-600 @ 600/6.3... the sparrow was at ~ 18ft.
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I must say I very impressed by the performance of the sigma 60-600mm. I didn't think it'd do so well!

perhaps the lens for OP to upgrade to.
 
nandbytes said:
sigma is definitely better than the original tamron. The G2 version is supposedly improved upon the G1.

Besides those scores which I assume you got from dxomark(?) should be take with a large grain of salt. There are many inconsistencies.
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I found similar results (MTF 50 Imatest results), just not on the specific body.
The point is, with the high resolution sensors it's usually the lens's max capability that is the limit. Sensor MP's don't often make much of a difference. It is quite possible that a hard crop from a sharper lens can have the same IQ/recorded resolution in the output image.


nandbytes said:
I must say I very impressed by the performance of the sigma 60-600mm. I didn't think it'd do so well!

perhaps the lens for OP to upgrade to.
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I'm quite impressed w/ it as well.
But something else is going on, and until that is figured out an upgrade could be a complete waste.
 
sk66 said:
But something else is going on,
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I have this feeling too if I'm honest, I'm suspicious of processing, saving files and uploading, though I may be way off the mark with those aspersions.

Every day is a school day and I could still have some way to go with my photography technique. (y)
 
sk66 said:
I found similar results (MTF 50 Imatest results), just not on the specific body.
The point is, with the high resolution sensors it's usually the lens's max capability that is the limit. Sensor MP's don't often make much of a difference. It is quite possible that a hard crop from a sharper lens can have the same IQ/recorded resolution in the output image.

I'm quite impressed w/ it as well.
But something else is going on, and until that is figured out an upgrade could be a complete waste.
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well in general terms if you increase the sensor MPs even with a telezoom like tamron 150-600mm you will get better results (perhaps not as much as you would with an excellent teleprime) at the same time putting a better optic on the same sensor would also result in better pictures.
Ideally you'd want to do both!

the above picture has some camera shake with noise reduction applied I think.
 
nandbytes said:
the above picture has some camera shake with noise reduction applied I think.
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Yes, both, I have noticed my pulse is causing the camera (sturdy tripod, locked gimbal) to wobble. Not a huge amount of NR but I will check. I think one of the biggest causes of the mush is the upload, one of the things I'm suspicious of. See the text? It's not crisp at all. This could lie with the way I save files for here, I will look into that.

I've enjoyed this thread, it's been very enlightening and I need to sort my technique and for now at least, forget about the 5Ds as a back up, maybe altogether. Lenses are now more likely than a back up body but there are other things that need indentifying and fixing first. (y)
 
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nandbytes said:
well in general terms if you increase the sensor MPs even with a telezoom like tamron 150-600mm you will get better results (perhaps not as much as you would with an excellent teleprime) at the same time putting a better optic on the same sensor would also result in better pictures.
Ideally you'd want to do both!

the above picture has some camera shake with noise reduction applied I think.
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An increase of MP always gives an increase in recorded resolution... but it's more due to an increase in oversampling and much less than the native increase. I.e a doubling of sensor resolution might gain only 10% in recorded resolution...
 
Dale. said:
Again, for reference but I'm happier. Much closer this time too, so less of a crop, within 12 feet now and it was also skipping about on my fabric pop up hide, inches above my head.

The best of the light was gone for this, it was much better earlier, maybe even too good as I struggled with the whites on my other image posted earlier today.

5Div, Sigma 150-600C, 600mm, f6.3, iso 1250, 1/1000sec.

This one has had too many sticklebacks me thinks. ;)

View attachment 260376
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This photo given the distance and lenses doesn't look crisps to me, more like heavily cropped or heavily noise reduction applied. Can you try with your Canon 100-400mm at similar distance?
 
I think that you'd learn much by sticking a tin of beans at kingfisher distance and then working through the whole capture to processed image procedure to see where things start to do awry. Use your various lenses and whatever software options you have and see what works best.
 
Bobsyeruncle said:
Probably because Dale uploads direct rather than linking from Flickr.
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Yes, that image was uploaded direct, not linked from Flickr. I will put it on Flickr later for comparison.

There is an image from yesterday in the birds forum that is linked from Flickr for comparison in the meantime. That one is a lot crisper here and even more so on Flickr. :)
 
Dale. said:
That one is a lot crisper here and even more so on Flickr. :)
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...which starts the hare of rendering engines running. Let battle commence! :naughty:
 
Canon Bob said:
I think that you'd learn much by sticking a tin of beans at kingfisher distance and then working through the whole capture to processed image procedure to see where things start to do awry. Use your various lenses and whatever software options you have and see what works best.
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I will definitely try this and give it the same treatment that I did the kingfisher. (y)
 
Dale. said:
Yes, that image was uploaded direct, not linked from Flickr. I will put it on Flickr later for comparison.

There is an image from yesterday in the birds forum that is linked from Flickr for comparison in the meantime. That one is a lot crisper here and even more so on Flickr. :)
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The one on flickr looks much better, but I would say it is back focused slightly.
When you have less than a half inch of DOF the placement becomes critical; and even the play/variance w/in the AF system can become apparent/problematic.
 
sk66 said:
The one on flickr looks much better, but I would say it is back focused slightly.
When you have less than a half inch of DOF the placement becomes critical; and even the play/variance w/in the AF system can become apparent/problematic.
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Maybe IS switched on the tripod isn't such a good idea? I can see movement through the viewfinder, even my hearbeat is causing shake, albeit quite minimal but enough to soften things at relatively low shutter speeds. I switched IS on to try and combat that.

I will also check for backfocusing.
 
Dale. said:
Maybe IS switched on the tripod isn't such a good idea? I can see movement through the viewfinder, even my hearbeat is causing shake, albeit quite minimal but enough to soften things at relatively low shutter speeds. I switched IS on to try and combat that.

I will also check for backfocusing.
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Sigma does not have a "tripod mode" for the OS, so using OS may be detrimental. Your best bet is to try to avoid slower shutter speeds... when you can't, shooting in bursts of ~3 images can help (a lot of the movement is imparted with the first image).
 
sk66 said:
Sigma does not have a "tripod mode" for the OS, so using OS may be detrimental. Your best bet is to try to avoid slower shutter speeds... when you can't, shooting in bursts of ~3 images can help (a lot of the movement is imparted with the first image).
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From Sigma's own advice page....
The vibration caused by the firing of the shutter and the movement of the mirror is transferred to the tripod. The characteristics of these movements are different to those experienced during hand held photography and the OS system cannot compensate for them. If you wish to use a tripod, please switch off the OS function.
 
What are the thoughts on the 600f4 mark ONE? Any quirks it might have or things to look out for? I'm guessing it's still 'better' than my 150-600 and would be able of resolving all the megapixels my 5D has to offer? I love the Sigma, but.

It's still an idea but a mk1 might be in reach (used) if I can move some gear to offset the outlay. I've not done the numbers yet but I may be able to make it work, they seem to be around £4k for a decent used example.

Thanks.
 
I've had a 600/4 MkI for the past 11 years. I'm sure that the more recent versions have optical improvements (and weight benefits) but they've not been spectacular enough for me to open my wallet.
 
This might start another debate, but the 600 is out of reach, for now at least. I could compromise and get a beat up example for £2.5k but I think I may just hold out for now, save some pennies and get a newer version. My main consideration is difficulty in getting a Mk1 repaired, should it fail. I'm not ruling out a Mk1 but I am going to take the penny saving period to think about things.

In the meantime, I have considered the 2x TC, a Mk2 or Mk3. I know there are lots of compromises involved though and even this way of doing things is still being thought about. My main concern is aperture values, my 150 to 600 would become f13 at the top end, hmmmm.

I have a 100-400L though, which wouldn't be quite as bad and better glass too.


I'd like to have the 600, I think it would suit the 5D well but cant see it happening in the short term.
 
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I dont think you really need a 2x given how close you are nowadays unless you want head shots.

However, if you do, you must get the mk3 version which is a substantial optical improvement on the mk2 and will be a huge plus with af once you get a mk 2 tele

Mike
 
pooley said:
I dont think you really need a 2x given how close you are nowadays unless you want head shots.

However, if you do, you must get the mk3 version which is a substantial optical improvement on the mk2 and will be a huge plus with af once you get a mk 2 tele

Mike
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I would like to be a little closer to the KF Mike, I'll hopefully be working on that tomorrow. I'm also going to work on nailing the focus, which if I'm honest, is where I'm not quite nailing things and might be the thing I need to work on more than getting closer. I would expect more clarity in the most recent images. I may switch to the 100-400 tomorrow, at least I shouldn't be able to blame the glass or camera then as both are better at photography than me.

One other reason for the 2x would be the SEOs, which are now back at the spot they were at last year. It's a huge area, so setting up is hit and miss as they could be active anywhere over a few square miles. They do like one area but even that is big. I did notice last year that they regulalrly used a few posts and fallen trees to perch at but they're spoilt for choice. there were times I wanted more reach then, I only had the 100-400 at the time, which is one reason I bought the 150-600.

Hopefully, KF tomorrow, owls Sunday.
 
sk66 said:
That would be a huge hit... I would expect it to be pretty useless.
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It's a concern, for sure, I think it would stretch even the 5d's ISO performance unless the light is excellent. Not forgetting the effect on the background.

I still have the 300f4 though, as well as the 100-400, which should make the most of the sensor, even with the TC, my only way to 600mm with Canon, for now at least.
 
Dale. said:
It's a concern, for sure, I think it would stretch even the 5d's ISO performance unless the light is excellent. Not forgetting the effect on the background.
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The main issue is going to be with autofocus, speed/accuracy/function. The longer FL with TC will have less DOF (~ 1/2).
 
sk66 said:
The main issue is going to be with autofocus, speed/accuracy/function. The longer FL with TC will have less DOF (~ 1/2).
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absolutely, I have a Sigma 1.4x and the lens will AF at 150 but hunts beyond 300 then not at all at 600.
 
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