In The Name Of The Dummy

R

ruben

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So I got a bump on my head and purchased that Canon Powershot A590 IS.

In fact it was a redressing bump as by the begining of 2009 I am purchasing my first digital camera.

And furthermore, I have the nerve to ask a couple of questions, I have not found the answer in the manual, which may make you either laugh or think I am pursuing a provocation. But within the redressing bump it seems I got, this is one of the few times when my purposes are purely informative.

So my first question concerns the resolution, as seen from the printing side. Let's compare my new 8 megapix camera with another cheapo of its time: the small Canonet QL GIII.

Let's assume I make a good ligthened image with the A590 IS, using the ISO 80 and superfine mode (7,5 mpxls). According to the manual I can have a print of about A3 size. And I can have it even with less megapixels, but let's take the most favourable settings.

A3 means 42cm x 66 or sixty something cm. With a decent iso 100 film exposure, an enlargement of a TMX frame will look somewhat grainy. The size is big. This goes for the film source print and Canonet QL.

Now, is it true that a comparable size (A3) resolution-sharpness printed enlargement could be obtained from the digi A590 IS (the enlargement made at a pro lab)?

Kindly give me your opinion. I tend to think that the resolution of film will surpass the digital 8 mega of my camera. But the question I am asking is at what PAPER PRINT SIZE my digi will match the resolution of the low ISO/Canonet QL GIII ?

My second question refers to the lens and aperture. In analogue photography we were used to the middle of the scale aperture being the sharpest, usually the f/8. But in my digi the f/8 is the smallest. Does the same old analogue rule still applies here (middle of the scale aperture = best one) ?

Cheers,
Ruben
 
1) Mid scale (lower than f8) will be your sharpest aperture.

2) Print size depends on a lot of variables. If you used Velvia, properly exposed in good light, on a tripod, you could easily out print a canon A590 IS. BUT here is the thing: we are talking about using a tripod! For hand held photography you will find, in good light, your little canon has an advantage called Image Stabilization. This, in effect, allows you camera to be more stable and have less motion blur. So, in summary, whereas the lens is more likely better on your Canonet, and with the proper film and tripod you could easily out resolve you A590 IS, in practice your A590 IS will probably have sharper pictures hand held in good light when the shutter speed is a little lower.

In summary: IT depends.

I know that a DSLR is a totally different beast than a A590 IS, but I printed a 20x30 inch photo from a cropped picture from my Canon XTI (10 Mp) and I was amazed at how well it turned out. I do not think a 35mm film shot would have looked as clean.
 
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I can't answer the highlighted question, but I was given by my kids a 4MP P&S in 2004. I still use it. But when I first used it, I put it on a tripod and used the self timer to expose. I blew one of those up to 8x10 and it was surprising how good it was.

2653600191_e04e79af4d.jpg


Here is a way to see it larger:
http://www.flickr.com/photos/carter3john/2653600191/in/set-72157606078956925/
 
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Rueben - I too have joined the A590IS parade and am astounded..

It's my pocket camera and I'm amazed at the quality it can produce.

Especially since I've added a grip (small handle) to the tripod socket.
 
regarding your question #2, the same rules of analog photography do not apply (middle apertures or smaller being optimal), especially for a small sensor (tiny) digital like the A590IS. When you use f4.5 or smaller, you will encounter a problem called diffraction which will have a negative impact on sharpness as the aperture gets smaller. In practical terms, you may or may not notice this effect. It depends on your subject matter, conditions, and other settings.

Please see this page to read more about it: Good article on digital sensors.

Hope that helps a bit,

--Warren
 
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newspaperguy said:
Rueben - I too have joined the A590IS parade and am astounded..

It's my pocket camera and I'm amazed at the quality it can produce.

Especially since I've added a grip (small handle) to the tripod socket.
Click to expand...

Hi Rick,

Did you add the bracket first of all for gripability of a dwarf camera, or, first of all for stability of the camera ?

Cheers,
Ruben
 
Yes, and yes. I added it for a better grip without sacrificing "pocketing"
and discovered the added benefit of much more stable shooting.

I used a small bakelite handle from some sort of old electrical controller arm
that I had in one of my many "junk" boxes. I'll try to remember to post pix later.
 
This is about VARIABLES. Regarding Printing, I have but little to say; I don’t print too much these days. When I had a B/W wet darkroom, I got quality 16x20 inch prints from Tri-X developed in D76 and D23. My Omega D2 enlarger [now in storage] has a cold light head.

A very satisfactory 11x14 inch color print of the Tel Aviv seashore, was done a couple of years ago from a digital card reader/writer; the original CD was from Fujicolor 200... exposed in an Oly 35 RC. Even if your original source is film, nearly all labs are printing from digital media.

On to Ruben’s 2nd question about middle aperture settings in the A590 IS. Here are more variables. Given a well lit exposure of a subject at ISO 80, how is that exposure being made? Is the camera on tripod, or is the photographer using a grip on a small P & S [as suggested above]? Is Program Mode, Aperture Priority or Manual being used?

Another variable is, what Lens? Ruben’s A590 is 35-140mm equivalent. My SD800 is 28-105. In another digicam some years ago, I had the 35-140, and was very disappointed. Apparently Canon did their homework, and improved this lens. For sure something has changed, if you guys are so very pleased with A590 image quality.

Having had some 5-6 Powershots in half a dozen years, I’m quite comfortable with the Canon Menu settings. My much used and loved SD800 IS is on ‘P’ most of the time. With the meter set to Evaluative [matrix] which is Canon’s Default, or even Center Weighted, the camera will decide very accurately, what the best exposure is. I’ll go to ‘Av’ or ‘Tv’ on special occasions.

Note that these cameras are IS, or Image Stabilized. Often, I’m shooting at ISO 200 or 400 indoors, and a blinking orange led and low shutter speed warning are calling for my attention. The IS makes for a sharp image at 1/10 of a second, if I’m braced and steady. The lens is usually wide open at f2.8, and I’ve gotten some great shots at max aperture.

Yet another variable, is Resizing. If one is “shooting at the top” with an 8MP digital [Large/Superfine in Canon], the Original capture will be over 3000 megapixels on the long side, and it's 2.5MB or higher in the PC. Most of us do Resize. When this is done, the pixels within the image are rearranged. That’s why a bit of digital Sharpening goes with Resizing. For Printing, the edited image in the memory card for the Lab, is at least 500k or higher. Digital pix posted in Flickr, are often 1024 pixels on the long side.

Finally, just one more variable. Most P & S digicams, have tiny 1/2.5 inch sensors. Noise is evident at ISO 200 and above, and “NR artifact” cuts in. This is in-camera Noise Reduction at higher ISO’s, and it causes a certain amount of image degradation.

NO dummy, Ruben, just new learning here. Oh, before I forget... for sure I'm aware of my camera's Settings, usually via the Fn function button. And, the beauty and joy of P & S photography is: You shoot, and don't have to think about this stuff
too much. :rolleyes:

Cheers, Mike
 
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