Pixel Question For Large Prints

[Nightsblood]

This is the first in a long line of questions Ive got but, I'll start here. Im looking to get started in photography and dont know how far I want to take it. This is killing me as far as choosing my camera. I checked out the offereings from Canon and Nikon and find, in general, I like the feel of the Canons better. All else basically equal, I think I'll probably be a new recruit for the Canon army. BTW, it was the 40D. Nice camera.

Anyway, what I was wondering, I would like to possibly turn some of my photos in the future to large prints. Something that could be framed, basic poster size maybe. As far as pixels go, is there a minimum number that would be required to get good clear blown up photos?

This photography thing is certainly complicated for the newbie. THis forum appears to be a great place to learn. THank goodness for forums like this.

 

[WDodd]

Welcome to the forum!

Great choice on the 40D that is a future upgrade for me hopefully.

You should have no problem blowing up really large at least 20x30 not cropped. I have gotten images as large as 11x14 with the 8 megapixels on my XT.

 

[Sw1tchFX]

megapixels mean nothing.

 

[EOS_JD]

Not sure I'd agree MegaPixels "mean nothing" (especially if you want VERY large prints). The more pixels the better the quality will be at large sizes. But the 40D will be able to produce huge prints (way bigger than 20x30 if required) at excellent quality.

 

[Nightsblood]

Ok, thats a little off my decision plate. Choosing a kit sucks! Im steering towards either a Canon 30D or 40D. THere is soo much to consider and soo much to read. Im BURNING OUT!

Help a brother out. Im figuring with the 40 out now, the 30 price will drop. Is this the norm? I dont want to spend a ton of money but, I really like the feel of the Canon 40D and thats something I want to shoot for but, might edge towards the 30, depending on what happens with price.

 

[EOS_JD]

30D is a great camera too. I use the 20D and love that.

 

[WDodd]

megapixels mean nothing.

I wouldn't agree either. More megapixels = greater noise in some cases and larger images. This can help with larger prints or cropping and getting large prints.

 

[EOS_JD]

The noise issue isn't so much a problem with new dSLRs. Even although the 40D has more Mp than the 20D and same size sensor, noise is lower on the 40D....... Although it's not really that bad on the 20D

 

[JIP]

megapixels mean nothing.

care to explain that???

 

[Sw1tchFX]

OK, i'll explain why megapixels for the most part mean nothing.

Megapixels should be your last concern when deciding on any modern camera.
For arguments sake, if Nikon made a 25MP full frame SLR that was exactly like the D3, for the exception of megapixels, I would choose the 12 megapixel one. Why not the 25 one? Because of optical limitations, and it would do more harm than good in post production. A small-format 25 megapixel sensor will show more lens issues than a small format 12 megapixel one because the photosites are smaller. Not only that, but having double the megapixels doesn't mean your images are going to be double the size. There is practically no difference between 6 and 10 megapixels. Nobody would even be able to SEE the difference when printed, even at 20x30! And if you're printing that size or larger than that consistently, than you shouldn't be shooting small format digital.

You don't need 20 some-odd megapixels to make beautiful prints, you need sharp lenses, and good technique.

For all intents and purposes, a 20x30 print from a 6 megapixel small format camera would look better than that same print done with a 45 megapixel one. That increase in image size, will show more of your lens issues instead of resolving more detail.

It's one of the reason's why modern P&S camera's images look like junk. They have 10 megapixels stuck in a sensor smaller than your pinky fingernail with dark lenses. If P&S's still used 1-3MP sensors with todays noise reduction, they would look immaculate in comparison to any P&S today. They would be sharper and cleaner, and would make much better prints.

So in conclusion, Small differences in pixel count, 5 and 8MP, are unimportant because it's like square footage. It only takes a 40% increase in linear dimensions to double the megapixel count. Doubling megapixel count only increases the linear resolution by 40%, which is pretty much invisible when printed.

 

[Jon, The Elder]

Nightsblood.....don't get too far afield here. One question leads to another and pretty soon confusion reigns.

We shoot for money. We use a 20D for 'posed' shots. My wife uses another 20D for her stuff. I have a 30D that I use for my work. The 40D is a bit of an upgrade in certain areas. You can't go wrong with any of the models.

As mentioned above, it is more a function of the lens used than any other single factor. This is where many 'noobies' make their first big mistake. The bulk of the budget is spent on the camera body, with secondary importance given to the glass. Consumer quality lenses just do not give you the IQ that better lenses are capable of.
Way to much "blame" is given to cameras, when it is the operator failing to do their part. Consumer glass is "blamed" also. Well, in general you do get what is paid for.

As to 20x30 prints.....how realistic is this goal? Are you expecting the same 'look' as a 5x7 held at arms length? The word 'poster' is not the same as a print of that size.

 

[EOS_JD]

Megapixels should be your last concern when deciding on any modern camera.

I don't disagree too much with this but those extra pixels certainly can help at times.

For arguments sake, if Nikon made a 25MP full frame SLR that was exactly like the D3, for the exception of megapixels, I would choose the 12 megapixel one. Why not the 25 one? Because of optical limitations, and it would do more harm than good in post production. A small-format 25 megapixel sensor will show more lens issues than a small format 12 megapixel one because the photosites are smaller. Not only that, but having double the megapixels doesn't mean your images are going to be double the size.

You are over exagerating things a bit in terms of what is available to the OP. you are right in your description but wer're not comparing 25Mp cameras with 12Mp ones.....

Better to take real world examples in the range the OP is looking at. Take the Canon 10D (6mp camera) and compare that to the 40D (10Mp camera).

Now although it has the same size sensor, the 40D has an extra 4 megapixels crammed into that space. However the 40D will still outperform the 10D in almost every area of image quality (noise, colour, contrast etc) because of the advances in technology. Advances in technology will continue.

I'm not saying megapixels should actually be used to select your camera but I disagree that size doesn't matter. You are right in saying that you can get great prints from a 6Mp camera and that the size difference is not huge but I still would rather have a better quality camera together with more pixels......

So I recon a 20x30 print from a 6 megapixel 10D will not look as good as a 20x30 from a 10Mp 40D (all other things being equal) for the above reasons and I'd be able to print it at a higher resolution (with the aid of the extra pixels).

So in conclusion,

differences in pixel count, 5 and 8MP, are unimportant because it's like square footage. It only takes a 40% increase in linear dimensions to double the megapixel count. Doubling megapixel count only increases the linear resolution by 40%, which is pretty much invisible when printed.

Depends on how big you are printing I guess..... For small prints you'll not notice but when going large those extra pixels will help.

 

[grahamhunter2001]

Having literally just got some 20x30 inch posters made up from 5MP P&S (Canon Ixus 50) pictures I can say they look great and lets face it with a poster that size you're hardly going to be looking at it with a microscope for the pixels. I did do some post-processing in photoshop to upscale the image using the bi-cubic smoother for the printing process though.

 

[SPYderBra]

When I print 3x9 METERS prints (in a decent focused picture, of course) megapixels make a lot of difference...

For a small size it really doesnt matter since most likely it will be more limited by the printer than the image itself.

 

[Nightsblood]

Ok, I have heard the "right lense" argument and that most of these kits are coming equipped with, not so great lenses so. THe question then falls, would I be better off buying a less expensive body only and invest the remainder of the money in a better, more suitable lense.

I really like the feel of the Canons so, I think Im gonna stick with them. Im most interested ,right now, in shooting landscapes and possible some of the kids portraits type stuf, mostly landscapes. Would I be better offf picking up a 20D body with a better lense or the 30D with a little better lense then the 18-55 they offer? Is the 20D outdated at all or will it do the job for landscape work, with a really good lense?

These are some setups from Amazon I found, but I havent researched lenses in depth yet. Depending on the replies to this, thats the next stop on the learning train.

Canon 30D
Body Only - $978
18-55 - $1150
17-85 - $1514
28-135 - $1284