Go Back   Steve's Digicams Forums > Digicam Help > What Camera Should I Buy?

Reply
 
Thread Tools Search this Thread
Old Oct 10, 2005, 4:20 PM   #21
Senior Member
 
Join Date: Jul 2003
Posts: 676
Default

Sorry, I'm clueless concerning the remote capture software.
lucky2505 is offline   Reply With Quote
Old Oct 10, 2005, 4:22 PM   #22
Senior Member
 
Join Date: Jul 2003
Posts: 676
Default

It seems to me that you might be able to bypass a PC with this camera.
lucky2505 is offline   Reply With Quote
Old Oct 10, 2005, 4:45 PM   #23
Junior Member
 
Join Date: Oct 2005
Posts: 13
Default

Following some DSC-R1 links I think I came across the proper way to describe a key feature that I need:
low luminance noise on black object on high ISO ;-)
Nicely illustrated by the comparison of the DSC-R1 to the Eos 20D at http://www.dpreview.com/articles/sonydscr1/page10.asp
With the Eos, black is still quite black at ISO 3200, while the DSC has a lot of noise that would obscure my precious gel bands ;-)

Which camera would give me what that Eos does or even better?
Thanks
Andreas
molecularbiologist is offline   Reply With Quote
Old Oct 10, 2005, 6:42 PM   #24
Junior Member
 
Join Date: Oct 2005
Posts: 1
Default

I read through most of the posts quickly; I know you don't want to buy a large system like a Fotodyne, but have you checked out the systems put out by Kodak?¬* I assume you know about them, but just in case, Kodak makes a EDAS system.¬* The newest version uses firewire and is very nice, but the system we have is still pretty quick through USB.¬* It does go through a computer (Great¬* for archiving) and the Kodak gel imaging software is very nice--will do more than what you want from the sounds of it, but can, for example, size unknown bands based on a standard and quantify based on a standard also.¬* One thing I really like is to invert the image, so the bands are black and background is white, which uses less ink.¬* ¬*You can, from the computer, alter exposure size (zoom) and exposure time.¬* It also comes with appropriate filters for ethidium bromide and syber green florescence.¬* I am sure you can frankenstein your own system, but compared to a fotodyne or such a system with a "live" image, the kodak systems are very affordable and I like the flexiblitity of quickly choosing gel size, exposure, and annotating the images, and having the transilluminator covered so I'm not soaking in the UV myself.¬* All that is to me very much worth the price, which is a bargain in molecular biology land.¬* If you still prefer to build your own, my kodak system is based on the old DCS260 and the photos are publication quality.¬* you can look up its specs and see that it is nothing extraordinary, so I am sure you can use just about any descent camera you want.¬*
LJ66 is offline   Reply With Quote
Old Oct 11, 2005, 7:22 AM   #25
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

Andreas

I'm not ignoring this thread.

I spent a lot of time comparing images from a variety of models yesterday, looking for characteristics that may be better for your types of images, and I still haven't drawn any firm conclusions. Dynamic range is very hard to judge (which is what I'm primarily looking for, but not necessarily just in the highlights).

Most of the sample images you see in lower light are not using very consistentexposure between models. So, that makes it much more difficult to judge. Also, some models are better at more dynamic range in the highlights area to prevent clipping there. I'd love to have the exact subject and conditions you're using, with a variety of popular models to test with. The differences could be interesting.

The Fuji S3 Pro is a good example of a camera that's betterthan most other DSLRsfor reducing cllippingin the highlights, probablydue to tone curve differences and the way the ratio between thetwo different photosite types are being applied in processing (probably about 1/16of the data comes fromthe photosites responsible for highlight detail in this particular model, which uses an unusual sensor design with two different photosite types).

I'm looking more for betterperformance in the shadows with most of the highlights properly exposed, in low light, not typical outdoor scenes (but also comparing some raw images processed differently for a better understanding of what may work well in raw, too). My opinion won't be very scientific -- it will be basedmore on what I'm seeing as general characteristics of a sensor,based on my eyes versus measuring brightness of different areas in an image.

Some of the differences you see arejust the way the images are being processed (either in camera or via 3rd party software tools for conversion from raw), making it even harder to judge sensor quality in this area.

I'll try to have an opinion in the near future (and take any opinion you hear with a grain of salt,especially mine, as most of them are likely to be biased).


JimC is offline   Reply With Quote
Old Oct 11, 2005, 9:16 AM   #26
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

molecularbiologist wrote:
Quote:
With the Eos, black is still quite black at ISO 3200, while the DSC has a lot of noise that would obscure my precious gel bands ;-)
You won't need to be shooting at ISO 3200 from what I've seen so far. For example, with the G6 sample you posted, you probably would have gotten a muchcleaner image by using a 4 second exposure at ISO 50 versus a1 second exposure with Auto ISO (which probably bumped it up to ISO 200, but unfortunately, Auto ISO doesn't record the speed used in the EXIF with this model).

You could have probably exposed it a little brighter, too (although you have to be careful with the highlights if you need them, as some areas are already starting to clip).

Now, I'm not saying the EOS-20D wouldn't be a better choice. You may also want to stop down the aperture more with a DSLR model for better depth of field (requiring longer exposures and/or higher ISO speeds). But, I wouldn't judge them by their performance at maximum ISO speed.


JimC is offline   Reply With Quote
Old Oct 11, 2005, 10:21 AM   #27
Junior Member
 
Join Date: Oct 2005
Posts: 13
Default

Thanks again for investing so much time into my question.
When referring to the Eos20 at ISO 3200 I did not mean to say that I need an ISO that high at all cost, but this type of noise at whatever setting seems to be where the 667 film was hard to beat, and where most digital solutions loose out.
It is interesting that there seems to be no hard numerical standard parameter which objectively measures these noise levels.
Also interesting to learn about all this, I am beginning to like this field ;-)


As for the Kodak system, thanks for the info, LJ66. Do you happen to know if the new GelLogic system is also built around a consumer camera? I am aware that older systems were built around the DCS290 and wanted to set up something similar, just with a more modern camera. I agree that the commercial setups are not that expensive compared to other equipment we are playing with, but as we have all the items other than a new camera I am just too stingy, I guess ;-)
Cheers
Andreas
molecularbiologist is offline   Reply With Quote
Old Oct 11, 2005, 11:01 AM   #28
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

molecularbiologist wrote:
Quote:
I am aware that older systems were built around the DCS290 and wanted to set up something similar, just with a more modern camera.
Some of the older lower resolution models were not too bad from a dynamic range perspective (probably because they were only using 2 Megapixels in sensor sizes we're trying to stuff 7 and 8 Megapixels into today). These models lacked the "Dark Frame Subtraction" noise reduction systems you see on modern cameras to map out hot pixels during long exposures, though.

I can remember when PC Magazine selected the Kodak DC280 as "Editor's Choice" in an issue comparing some of thedigital cameras at the time (November 1999). I've still got a copy of it here somewhere. One of the things they noted in this particular article was this Kodak's ability to pull out more detail in shadows compared to some of the other model's tested. That could have been the type of image processing/contrast curves used in camera, too.

Another benefit of some of the older Kodak models for some applications, is the Digita Operating System someof their cameras used. This allowed users or developers to write scripts and applications that ran in the camera.
JimC is offline   Reply With Quote
Old Oct 11, 2005, 11:27 AM   #29
Junior Member
 
Join Date: Oct 2005
Posts: 13
Default

I read about the Digita scripts. Is there any modern day version of this? We talk about late nineties like the dark ages here ;-)

Anyway, if cramming pixels might be part of the problem, should I be looking at a lowish-resolution SLR model then?

Best wishes
Andreas
molecularbiologist is offline   Reply With Quote
Old Oct 11, 2005, 11:38 AM   #30
Administrator
 
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,378
Default

molecularbiologist wrote:
Quote:
I read about the Digita scripts. Is there any modern day version of this? We talk about late nineties like the dark ages here ;-)
Nomodern cameras that I'm aware of still use it.

Quote:
Anyway, if cramming pixels might be part of the problem, should I be looking at a lowish-resolution SLR model then?

Maybe.... But, nobody is making them anymore (Nikon's D2H/D2Hs models are probably the largest photosites you'll find in a currentcamera without going to something even more expensive with a larger sensor size). :-).

You really need to take them on a case by case basis anyway (you can't always go by photosite size due to other design differences).


JimC is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 6:48 AM.