Excellent diagram Liam - as they say, a picture says a thousand words...

If I say 100% crop (or rather, I think, 100% cropped), I mean that the image shown is shown at 100% size (i.e. no resizing of the original pixel dimensions has been done), but then cropped down so that just a portion of the image remains, rather than show all 3008x2008 pixels.

For example:



Full frame



100% cropped


Maybe I've got the wrong end of the stick. I'd just say 'Full frame'.

But we know what you mean!

Dan

I reckon that sounds right. Of course, the advantage of the digital body is that to get that increase in magnification (on the output ), you don't suffer from a loss of light (as you would using a 1.5x convertor) and you can still focus on infinity (which you would lose if using extension tubes).

I'm doing so much more macro work now I'm digital, just because it doesn't cost anything to get the right shot, so you can really devote a lot of shots to a subject, and I can happily use flash, which I was always dubious about on film.

I love digital!

Dan

It made sense?

Dan

Well, I did say "This is an odd one, and depends on how you look at it!"

Drew, the minimum focusing distance of the lens is not going to change - it's the same lens whatever body it's mounted on, after all.

The reaon you could see 65mm width on your MZ5N, is because that's roughly twice the width of your 35mm film (okay, that would be 72mm, but you'll lose some from the edges of the viewfinder, you don't see the full 100%).

The reason you could see 42mm when you used your istDS, is because that's roughly twice the width of your sensor (okay, that would be 48mm, but you'll lose some from the edges of the viewfinder, you don't see the full 100%).

It's twice the width in both cases because the lens give half life-size reproduction, the magnification ratio is 1:2. Therefore, every 2mm of subject is 1mm wide on your sensor/film.

So your lens, on both bodies, gives 1:2 magnification. But when you then view that (either as a print, or on your screen), the Digital body will show a narrower field of view, and hence the output will be more magnified.

So yes, in effect, you get more magnification with the DSLR. But it's because of the body (the smaller sensor), not the lens.

Is that any clearer? It's always much easier to explain things face to face, I have to admit - you can actually demonstrate things then.


When I got my Sigma 105mm macro, I had a similar thought to you - I'd got so used to this 1.5x factor with DSLR's that I thought "great, this 1:1 lens will be a 1.5:1 lens". When I got it home, I got a ruler out, looked through the viewfinder, expecting to see just 16mm (24mm/1.5), but it was 24mm instead, which was a surprise. But then I thought about it, and realised that the lens still gave 1:1 magnification, but the smaller sensor meant that the subject would fill more of the frame. A 15mm long bug was still 15mm long on the film or the sensor, it's just that there's less background shown on the DSLR.


Hope that helps! Just enjoy your macro work, I know I do.

Dan

Drew,

This is an odd one, and depends on how you look at it! Compared to 35mm film, you will apparently have greater magnification. If you have a subject that is 48mm long, on film the image would be 24mm, or 2/3 of the width of the frame (1:2 magnification). On your DSLR, the image would still be 24mm, but that would now be the full width of the frame.

The magnification at the taking stage is no different, it's still 1:2 (half life-size), but at the output stage (ie. if you made a 9x6 print, full frame from both film and digital), the magnification would be greater for the DSLR.

Does that make sense?

Dan

I spoke to Intro2020 earlier today (I work for Essex Wildlife Trust in a Visitor Centre, and we have an account with them, but it's only in the last couple of weeks I've even thought about getting Pentax's in to order, it's not a stock line we would normally carry, but getting things in to order isn't such a risk for a charity). Anyway, they're expecting a shipment of K10Ds on 15th November. All the kits (body + 18-55) have been allocated to dealers, but 'body only' is still available in this shipment, and they have another one due soon after. They're saying that demand has been high.

The guy I spoke to had had a play with one yesterday, and was impressed (but then he would say that). I'd like to see some high-ISO demo photos, all the ones I've seen so far have been 100-400 I think.

So, from what I was told, I see no reason why the cameras shouldn't be in shops by the end of November. Fingers crossed.

Very tempted myself - I get a 10% staff discount.

Dan

Aah, what's wrong with wasps? Well, there's something obviously wrong with that one

Beautifully sharp, especially as it's a 100% crop. Looks like it's definitely macro season again!

Dan

Bearing in mind the original subject title "Super Multi Coated Macro Takumar 1:4/50", perhaps I should have chosen my example mag ratio more carefully.

Ah, no, I wasn't saying 1:4 as in the aperture (f/4), but in a magnification ratio 1:4, so that images are a quarter of lifesize. If your Pentax 50mm macro lens says macro, then I have no doubt that it is capable of 1:1 magnification.

It's the 28-200mm zooms and the like that tend to say 'macro', then 1:4.

I wasn't casting aspersions

Dan