Talk to me about megapixels.

[intheflow]

usedtobesick has told me he wants to get me a good digital for Christmas this year, but I'm useless at translating camera specs into information I can use.

What I really want to know is, how many megapixels do I need so I could enlarge a shot to, say, 22x28 and not lose photo quality? Anyone have any experience enlarging digital shot to that size?

[F.Gordon]

1. I've gotten very clean/crisp 30 x 20 prints from my 20D

8 megapixel. But you need a lab that "knows" digital. Most don't. I use smugmug. They KNOW digital and use a lab in tennessee. Not to sound like I'm "whoring" for these folk....

Also. If you have a good RAW processor you can bump it up a notch. The processor I use saves my files in an uncompressed 25 meg tif file. I haven't tried using one of these 25 meg tif's yet for prints but I would think that even the local "chain" processing labs could do large prints with that.

What that helpful?
:shrug:

Sorry. I know NOTHING about print processing other than what people tell me they can and can not do.

[intheflow]

2. "Was this helpful?"

Um... yes and no. Was that the camera you brought to dinner? (And where the hell are those blackmail shots you took of us?)

What the Sam Hill is a RAW processor?

And how are you doing these days? Surgery complete, or still waiting? :hug:

[F.Gordon]

6. Ummm....

Yes, the same camera I brought in my "custom" beverage holder camera case. And do you really want me to post the blackmail shots? I'm not certain I want to expose what "F.Gordon" looks like quite yet. ;-)

Sam Hill? You've been living in Colorado too long. Next you'll be saying stuff like dag-nam-it.
:rofl:

A RAW processor, as I define it, is a software thing specifically designed to "process" RAW files from the digital camera. Check this one out that bvar22 mentioned awhile back that is FREE....

http://www.pixmantec.com/products/rawshooter_essentials.asp

I've gotten very good 30 x 20 prints off a 6 meg file, but most have been in the 8-9 meg range. Have read that some digital print processors can work off a 3 meg file for this same size. If you had stopped by the F-Troop house I could have shown you. Everyone that has seen them has been pretty impressed (or they're just blowing smoke up my ass).

Surgery? After surgeon beat the shit out of me for about 15 minutes he decided that he wants me to get a CT before he slices and dices. Then I found out that these "CT" things are expensive. Basically... I'm still waiting. Thanks for askin'. :hug: In the mean time I've stocked up on pain meds. I dread going through this shit. My stress level is through the roof these days. :(

[intheflow]

9. Well, you could email me the blackmail shots.

Although, really, you're not that hideous to look at! :P

I'm still totally confused about megapixels and whatnot. But you and bvar22 are both singing the praises of the 20D, so I think that's what I'm leaning toward. I want a Canon so I can use my existing lens collection.

Still not sure what the RAW thingee is, and probably won't have a chance to really check out the link you gave me until I get back home after Christmas. Time is limited here on Mom's computer.

Don't know what a CT is (I assume it's not Connecticut, although that would be expensive), but it sounds painful and unpleasant (kind of like Lieberman's state of Connecticut). Perhaps early in the new year, before I return to Mississippi, usedtobesick and I can do dinner again with you and Mrs. F.Gordon. I won't even ask you to share your pain meds. If you're up to it, of course. :)

[gulfcoastliberal]

15. I'm sorry to hear you have health issues.

I'm uninsured so I know all about expensive medicine. I getreally bad migraines all the time, usually a couple of vicoden will work but if not, I have to go to urgent care and get shots of toradol and phenergen. ~$150 a pop. But it beats going to the emergency room - I bet the $150 would morph into $1500 or more! I first startd getting the migraines when I was insured, so I've had CT scans, MRIs, seen a host of doctors and tried every migraine targeted drugs like Imitrex, cafergot, midrin, ad nauseum. None of them worked.

Wishing you all the best, and sending good vibes your way.

[Eurobabe]

27. try some magnesium

my friend gets migraines and she swears taking magnesium supplement has helped her. Just a thought.

Now back your regularly scheduled photos...

[Ms. Toad]

3. Keep something else in mind...

If you ever crop you need more mega-pixels in order to blow the cropped portion up to the size you want. If you crop out half of the photo and want to print it as a 5x7 you will need just as many mega-pixels as if you want to blow the entire picture up to 10x14.

(The sales people I talked to when I was camera shopping kept telling me I didn't need 4 mega-pixels because I generally don't want to make 8x11 prints, so I thought I'd mention this.)

[intheflow]

4. This is a very good point!

I do a lot of cropping with my photos, so this bit of info is invaluable. Thanks! :hi:

[bvar22]

5. This reminds me

This question reminds me of a sign that used to hang in automotive "SpeedShops" back in the 60's (and my hotrodding days):

SPEED costs MONEY!
How fast do you want to go?

I'm currently using a 4 megapixil camera, and I have been pretty happy with it.
I have never had too many megapixils, but I have occasionally had too few, especially when I wanted to crop some shots changing the point of interest.

In general, buy as many megapixils as possible.
"Digital Zoom" is a scam that reduces the # of available megapixils. (go for "optical zoom")
As Digital Cameras mature, the cost per megapixil drops (quickly), and the # of megapixils increases.
There is a point of diminishing economic returns when shopping for more megapixils. My current threshold, based on the size of my wallet, is 8 megapixils (the Canon 20D I'm buying). A few years ago, 8 megapixils was NOT available at ANY price.
Next year, 8 megapixils will cost less than this year.

[alfredo]

7. I heard that 16 mp is equal to 35mm.

is that the case?

[intheflow]

10. That's what I'd like, 35mm quality.

But YIKES! 16 mp must cost a brazilian dollars!

[alfredo]

11. I will have to wait a few years and be happy with my 5mp.

It's good for images up to 8X10.

[regnaD kciN]

26. It should work for a lot more than 8x10...

A good 5MP camera should let you print high-quality work up to 12x16 or 12x18 (depending on your camera's aspect ratio).

I've had very good results with 11x14 prints at Costco. I have yet to try one larger, but I would note that I also got a very nice 8x10 from a photo where I cropped a vertical image out of an horizontal one -- in other words, where I was only using about half of the camera's resolution.

[intheflow]

8. I'm thinking the Canon 20D is sounding pretty good.

But of course I'm totally frustrated by that rapid cost drop thing, too. The Canon I'd love to get (can't remember the model off the top of my head) has 12 megapixels and is, like, $3200! :eyes: And that's just for the body. You want a lens, it'll cost ya. x( So wallet is important for sure, but if I wait for next year, it'll never stop--because then I'll want to wait for the next year's model, a 15 megapixel or some such.

[alfredo]

12. The lenses for Canon are not too expensive.

I'm on my third Canon and I see no reason to change to another brand.

[intheflow]

13. I have two lenses for my film Canon Rebel.

I like that they can be used on a Canon digital body.

[alfredo]

16. That's what I am going to do.

I have my film lenses and will mate them to a body as soon as I can afford to do it.

[RagingInMiami]

22. The 5D

That's the camera I want also. It doesn't have that 1.6x crop factor, which in my opinion, is the biggest drawback about most affordable digital SLRs.

http://www.dpreview.com/reviews/canoneos5d/

[ConsAreLiars]

14. 22x28 is a large print and would normally be viewed from a bit further

away than a 4x6 or 8x10. For smaller prints 300 dots (pixels until printing) per inch is good, going over 360dpi means going beyond the resolving capability of the best human eye. For larger ones 200dpi is good enough for gallery grade work. This means a 22x200 times 28x200 pixels which is 4400 pixels by 5600, so a camera that gives you 4400 pixels on the shorter side would get you there. `The bad news is that works out to around 29 megapixels. The good news is that very most editing software will let you upsize photos using very effective algorithms, so that you can use lower resolution images and still get very good quality. High end digital printing services can do even better. I've seen 40x60 pixel web grabs printed at around 4x6" - about 10 dots per inch - using a software program designed to address this situation. Pretty crappy by portrait standards, but far, far better than the original would have suggested was possible.

There's a tutorial on that subject here: http://www.normankoren.com/pixels_images.html

[bvar22]

18. Great Link, ConsAreLiars!

:patriot:

[intheflow]

19. Dear me!

This is exactly why I have never really wanted to venture into digital photography before. I can follow your response, and bvar's below, to a point and then it all becomes technobabble to me. I'm good up to the part about editing software allowing me to upsize. Then I get lost.

But then, I've been shooting with film for about 15 years and I still don't fully understand f-stops, so I'm sure the problem lies within my totally techno-phobe self and not with you, the messenger. It'll probably be a few years before I can hope to do any gallery work, and maybe by that time I'll have figured out the practical application of what this all means. :)

*On edit: spell check is my friend!

[RagingInMiami]

21. You're like me

The technobabble just doesn't sink in. We're more right-brained people. Tend to learn more by visuals rather than reading an owner's manual or listening to someone explain it.

But the best thing about digial photography for people like us, is that you're able to see the photo as soon as you take it. So as far as f-stops go, you can experiment right on the spot and see instant results.

So I understood more about f-stops in a year of shooting digital than I did in the five previous years shooting film.

The other technical digital stuff becomes more understandable once you start doing it on Photoshop.

[RagingInMiami]

20. ConsAreLiars

You never stop educating us.

[ConsAreLiars]

23. I think we all get educated here.

I try to add what I can, and I've been playing with computers on and off since a roll of paper tape with holes punched in it served as a storage device, learning as little as necessary along the way, so I have some familiarity with the bit-byte-pixel stuff, and I got into photography before then. Even so, it took a while for me to figure some of the basics of digital darkroom work, and I have a lot yet to learn.

[RagingInMiami]

24. Then you might be the right person to ask this question

Do you know of any software that repairs raw files? I ended deleting a bunch of photos by mistake and when I ran "recover your photos" software on my memory cards, I was able to retrieve the files, but now I am unable to open them.

All I get is the icon.

[ConsAreLiars]

25. Sorry, I'm still behind the times and haven't encountered that problem.

I assume you've used whatever came with your camera and the free Corel RAW file editor that was mentioned here recently. If not, open a program designed to handle RAW format and see if it works. Also find out the file size and decide if it was in the normal expected range. A file size of 1KB tells you that there is nothing there. A file of a few hundred KB or more suggests you have real data. I would try Irfanview http://www.irfanview.com/ with the plugins mentioned on the left installed, and if that failed use something like fileviewer http://www.fileviewer.com/ to see if I could get any hints about what is actually there.

[bvar22]

17. From the link posted by ConsAreLiars above:

(and this info is a couple of years old)

"APS-C or Four-thirds sensor size. 5-12 megapixels. Sensor sizes from 22 to around 27 mm diagonal; half to 2/3 that of 35mm (43.3 mm diagonal). This means lenses designed for 35mm cameras have a smaller field of view; they have a "focal length multiplier" between 1.5 and 2. Although I originally viewed them as a stop on the way to full-frame DSLRs, I now realize they're here to stay. Their image quality equals or exceeds 35mm, and they're smaller, lighter, and much less expensive than the full-frame DSLRs (below). Several manufacturers now make lenses for this format: because they don't have to cover the entire 35mm frame they can be sharper, somewhat smaller and lighter, and (perhaps) slightly less expensive. And ultrawides are now available from Canon, Nikon, Olympus, Sigma, Tokina, and Tamron. My Canon 10-22 mm is equivalent to 16 mm in the 35mm format."

See the rest of this page at:
http://www.normankoren.com/digital_cameras.html