aperture help..

suggs

suggs

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Harry
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Yes
im finding that when in A priority and shooting with a D200 and 50mm 1.8 at say f1.8 and then again at say f5.6 the f1.8 a pictures seem lighter and a bit washed out lack of colour. I did have the iso at 100..

should i increase speed a bit or add a step or two of E/C ?

heres an example taken today within seconds of each other and same tree/light etc, but clearly ones got better colour?..


(1) f8, 1/125 iso 100


027 by harrylessman, on Flickr


(2) f1.8 1/2500 iso 100


024 by harrylessman, on Flickr
 
Sure it woulkd be pretty easy to boost the contrast and colours a bit in an editing software.
Im guessing the wider aperture shot is a faster shutter speed, so not as much light hitting the sensor, which maybe means it doesnt quite have the deeper colour of a slightly longer exposure with more light hitting the sensor.

That could be complete arse, but thats my logic :lol:
 
TCR4x4 said:
Sure it woulkd be pretty easy to boost the contrast and colours a bit in an editing software.
Im guessing the wider aperture shot is a faster shutter speed, so not as much light hitting the sensor, which maybe means it doesnt quite have the deeper colour of a slightly longer exposure with more light hitting the sensor.

That could be complete arse, but thats my logic :lol:
Click to expand...

I'd agree with that to be honest.
 
@1.8 the sky and the rest is slightly out of focus as the fine DOF is just over the tailed rat and the tree branch, its the bokeh effect of the lens (at wide apertures) that sofens and desaturates the OOF part. The in focus part, the rat and the branch are the same (saturation and sharpness) in each picture.

By the way u really did nail the rat, well done. I prefer the 2nd picture.

Tom,

I am thinking although the shutter speed is faster the aperture is wider, so more light can get through than at say F8, if you get me??? I know what I mean :lol:.
 
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The exposure is only slightly out, but the most likely cause is the diaphragm is not closing down to exactly f/8 due to mechanical innacuracy. The camera always sets the exposure at lowest f/number, and then calculates back to what it should be when the lens closes down.

It happens quite a lot at high f/numbers, when a tiny fraction of a mm out can make a visible difference, but less often at mid-range apertures. 50 1.8 is a cheap lens I guess.
 
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suggs I think the un-touched photo looks way more natural. The deepness of the blue sky in the 2nd PP'd photo make it look a bit fake to me. I like the sky in the first PP'd photo but it has a off-White Balance feel to it.

Def a great shot of that little guy though!
 
#1 is clearly EV13 and #2 would also be EV13 if shot at 1/2000, f/2.

Part stop values can be pretty confusing so I tend to avoid setting them (I have disabled them in the menu) but I'd imagine that the aperture increase from f/2 to f/1.8 must offset the shutter speed increase from 1/2000 to 1/2500 so you must still be "sort of" at EV13, so I'd expect the pics to be pretty similar but with differing DOF.
 
suggs said:
whats EV stand for exposure value?
Click to expand...

Yep that's right. It's quite a handy system for working out different combinations of shutter/aperture/iso for different light levels.

It's built on a "base" level of EV0 which is 1s @ f/1 @ iso100.

Not many people will have an f/1 lens so you will not often see this combination used, but you can see that your shot was shot at 13 stops higher - the shutter speed is 7 stops higher (1 > 1/2 > 1/4 > 1/8 > 1/15 > 1/30 > 1/60 > 1/125) and the aperture is 6 stops higher (1 > 1.4 > 2 > 2.8 > 4 > 5.6 > 8), so 13 stops higher in total hence EV13.
 
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A small difference in exposure between the two shots could be down to what metering mode you were using and what, exactly, you metered on. I'd be inclined to think that this was more likely for the difference than a change of aperture and subsequent shutter speed.
 
Scarecrow said:
A small difference in exposure between the two shots could be down to what metering mode you were using and what, exactly, you metered on. I'd be inclined to think that this was more likely for the difference than a change of aperture and subsequent shutter speed.
Click to expand...

Yes. In my reply above I was assuming (for some reason :thinking: ) that the camera was in manual. Probably rubbish ;) :D

It's only a slight change in exposure and could be down to all sorts of things. Thinking about it, the most likely cause is probably a slight change in framing of the full image which has altered what the meter sees, including more of the darker branches for example, when shooting in one of the auto modes.
 
quote " im finding that when in A priority and shooting with a D200 and 50mm 1.8 at say f1.8 and then again at say f5.6 the f1.8 a pictures seem lighter and a bit washed out lack of colour. I did have the iso at 100.."unquote

I would suggest set the camera to "vivid" as I presume the camera was set to "normal". check out in the menu
 
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still looking a bit over exposed to me, i never took this as im in it but i did set it up. f1.8 iso 200, WB Auto.

thinking maybe i should have messed with the WB a bit?..


008 by harrylessman, on Flickr


also took this one and colour seems much stronger, the red in the background is broken clays that are in fact bright orange, was a very bright but grey day today where these were taken..


025 by harrylessman, on Flickr
 
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