Question regarding ISO choices
- This topic has 14 replies, 4 voices, and was last updated Apr 14, 2006 at 1:21 pm by
.
-
Posts
-
Here’s the problem with auto ISO.
Say you are shooting in a normal outdoor light situation. If you were using ISO 200 film, typically you’d choose a mid-range shutter speed of, say, 1/125th and an aperture in the mid range of f/11 or f/16.
Now if you were in that same situation and you happened to have ISO 800 speed film loaded (i.e. two stops faster,) you’d have to compensate to achieve the same result by closing down the shutter speed to 1/250th and maybe bringing the aperture down another stop as well.
This is because ISO 800 speed film *exposes faster* than ISO 200 speed film, so you have to *give it less light* to get an equivalent image.
Most professional magazine work is done with Fuji Velvia ISO 50 chrome – a very slow slide film.
No, trumpy, the answer is I only recently realized myself what an impact auto ISO was having and switched back to all-200.
Zach
Trumpy,
A quick answer to your question is, “Use the lowest ISO possible for the lighting situation youre in”.
I would disagree with only one point Zach made – and that is that APS-sized sensors are “less noisy” than the full framed sensor Canon models.
Yeah, Richard is absolutely right here; I misspoke and remembered later but I didn’t go back and correct it.
Zach,
I am a member of Nikon Professional Services, but they dont tell me anything either.
My guess is no.
Hey Richard –
I lost a sale lately (“High Water” in the Photoblog) because my D70 couldn’t go double-truck and hit anything close to the 300 dpi asking range for American Angler. Do you know of any way to interpolate an image out of my camera up to 11X17 at 300dpi without looking pixelated?
Have you sold any double-truck images from your D200?
Zach
Do you shoot in RAW? And if so, what do you use for a converter?
I have only had the D200 for 3 weeks – and its a backup/second body.
Hey Richard –
I am using Photoshop CS2 to convert. Usually I just drag in the files to an archive hard drive, then import them into Adobe’s Lightroom Beta program, then scan through them and drag them into Photoshop, where I adjust exposure and eventually save in JPEG.
My calculations on the D70 are that at 3000×2008 output you only have 10-inches across on a long side. I published a full page shot in the current issue of American Angler (Ed Engle’s article, facing page, misattributed to my wife, Lauren), that was 11.5 inches on a long side. Just to get that full page you are already blowing up the image from 6 2/3″ on the short side to 8 1/2″, so we’re talking about more than a 100% enlargement for the two pager. (Although I could certainly do it with a panorama if I had time to set it all up).
However your statement that you’ve sold the D2x images in two pages gives me hope, since at 12 megapixels you’re seeing at least a 25% enlargement even with that excellent camera. (Hmm, wait, on second reading, do I have that right, or are you also limited to one full page as yet?)
This is as much a problem of convincing my editors that we can break the 300dpi barrier as anything, I expect, and I also know they have good reasons for wanting to keep it as close as possible to that 300 dpi level. This is why I hope the D3(X, H, whatever) will at least carry 16MP. That would be two pages at 300dpi out of camera with room for cropping if you needed to with a minor enlargement and a ton of room to crop into a one full page image.
Zach
Here’s an engineer’s explanation of why the Nikon approach might be better with respect to noise (warning, it is almost unreadably dense):
http://www.danblanton.com/viewmessage.php?id=63562
Zach
- You must be logged in to reply to this topic.