Higher ISO v Bigger Aperture

[infl3xion]

improve both so we get night vision

[TOM]

night time is best for mostly sleeping

[farmer_rob]

better [faster] glass gives you more options, i don't see how it introduces more complications.

OK - more options, but it may not solve the problem you have. And if you want/need f5.6 for your *desired* DOF, faster glass won't make a significant difference for the price. (refer to the thread I pointed at.)

that may be true in some instances, but i think it's a rather short sighted solution.

I did suggest in some cases, not all.

There is a lot of DOF at f/2 on a 200mm lens - because you have to stand so far back, DOF is quite huge. I've used it for indoor weddings and everything.

I'm sure it is a great lens with excellent applications, but if you refer to the thread I pointed out, you will understand why I am saying there are situations where the DOF is too thin, and hence the lens does not fit all the problems. (And, yes, there are too many generalisations - but I include "get faster glass" as a generalisation too.)

TOM & Pollen: Great shots BTW

[Othrelos]

As demonstrated by Leica photographers, never underestimate what can be captured in the available darkness of this world, Leica cameras can be hand held at substantially lower shutter speeds than traditional SLR based camera designs because they don't have that sharpness killing mirror flapping about. Though you don't really need a budget to support a Leica M9 and a noctilux 50mm f/0.95 to do low light photography, there are a few cheaper options that are as good. Pentax or Sony's offerings with decent intergrated body IS. Both Minolta and Pentax at one point produced 50mm f/1.2 lenses (pentax are apparently still making theirs) in combination with the IS in the camera bodies hand holding at 1/2 a second isn't such a daunting prospect. For slow moving or static subjects under low light, ISO and fast apertures aren't the only thing that has to be taken into account.

[TOM]

OK - more options, but it may not solve the problem you have. And if you want/need f5.6 for your *desired* DOF, faster glass won't make a significant difference for the price. (refer to the thread I pointed at.)

hey your two options here is to go with a slow shutter speed (it's a bit harder with an slr than most other cameras though) or ISO crankage, sure, but i'd love to have that fast option. distance is the biggest contributing factor for DOF of a given focal length, not aperture. at a moderate distance for any given focal length (say halfway between minimum and infinity), DOF isn't too much of a concern wide open.

[Othrelos]

Distance is the biggest contributing factor for DOF of a given focal length, not aperture. At a moderate distance for any given focal length (say halfway between minimum and infinity), DOF isn't too much of a concern wide open.

I don't disagree with your statement, however I will point out that DOF still can be quite shallow with f/1.2 lenses. Even at moderate distances, for instance on a D3s a Noct-Nikkor 58mm f/1.2 focused at 10m will have a total DOF of only 2.13m

[kiwi]

And 2.13 meters is enough dof for John Eeles lying flat, so, more than enough for most

[ricktas]

I don't disagree with your statement, however I will point out that DOF still can be quite shallow with f/1.2 lenses. Even at moderate distances, for instance on a D3s a Noct-Nikkor 58mm f/1.2 focused at 10m will have a total DOF of only 2.13m

I calculate that to 2.17m?

[MarkChap]

Over 2 meters DoF,
I would hate that to be how they measure the shallow end of a pool.

[TOM]

2.13m

actually less than that. the 2.13 or 2.17m is based on OLD film emulsion and OLD lenses, not modern Asph lenses with modern ag-x emulsions and solid state capture. if you wanted to print bigger than 8x10 and relied on those charts, you'd be pretty disappointed me thinks.

[kiwi]

Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

[ricktas]

Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

I agree, and I only use the chart as a guide. Not that I am going to measure my subject to make sure they are 2.17 metres. It gives me a general guide to work with

[Othrelos]

actually less than that. the 2.13 or 2.17m is based on OLD film emulsion and OLD lenses, not modern Asph lenses with modern ag-x emulsions and solid state capture. If you wanted to print bigger than 8x10 and relied on those charts, you'd be pretty disappointed me thinks.

based on a COC of 0.030mm 2.13m is what i'm getting for my DOF calculations. As far as I'm aware the vintage of a particular lens, or the emulsions used whether silver based or sillicon based sensors are variables that have a negligible effect on DOF. I have yet to be disappointed.

[TOM]

it's the COC that doesn't fly any more

[Othrelos]

it's the COC that doesn't fly any more

well it's a COC I still use with my full frame DSLR's and I haven't seen any particular reason to revise it, because I use DOF calculations to give me a ballpark figure of how much DOF I have to work with. Whether it is 2.13m or 2.17m I prefer to stick on the conservative side for my DOF.

[etherial]

Interesting though dof calcs like that, I don't believe that the sharpness is the same throughout that dof though that's not the theory

That's right, there is only one point that is the sharpest point in the middle of that quoted range for DoF calculators or charts. The range refers to an "acceptable focus or sharpness" which becomes subjective.

Anyway, this is wandering off topic. Bottom line it is horses for courses depending on your needs.

[TOM]

Cool, if you're happy with the results then there's no need to change.

[pollen]

I've never understood the point of DOF calculations for digital cameras, why not just use the LCD and DOF preview to check for the in focus area? It's far more relevant information than a theoretical calcuation. And where your camera doesn't have DOF preview, why not just zoom in on the LCD and check?

And if you don't have time to chimp, you certainly wouldn't have time to do a calculation!

[Cage]

Thanks for all the well considered replies.

To me, it seems that the most valid reason for keeping the big aperture lens is to get enough light to the sensor to be able to focus accurately, albeit manually.

That seems to be an area in which the various manufacturers have room for improvement. Although I've seem some good feedback from KatzEye users, it only seems like a 'quick fix' and not a 'solution'.

IMHO, bokeh and DOF are always going to be a juggling act. Bokeh, particularly, seems to vary from lens to lens in similar scenarios, plus it has the potential to be 'adjusted' in PP.

Like most who frequent AP, I'm looking for information to help me get the best results from the gear I have. At times I feel like I'm on 'the trail of the Grail'.

Maybe I'm destined to wander eternally in the ever decreasing COC, never enough light to enable me to focus clearly on what I seek, eventually to disappear into my own fundamental orifice.

Cheers

Kevin

[darkbhudda]

For gigs I usually have to use my 50mm 1.7 at ISO 3200 and 1.7 because of the bad lighting. Sure in a decade when I can afford a camera with ISO 2.5million I won't need such a wide aperture for the low light conditions but the shallow DOF will still be useful.