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10-28-2015, 05:58 PM   #121
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QuoteOriginally posted by CWRailman Quote
By the way, maybe it’s just a coincidence but I have recently noted several listings for complete multi lens Q7 systems on Ebay. Maybe owners are dumping while the dumping is good?
Well, either way it's a plus for me... If the Q line continues to developed (and I truly hope it does), I'll eventually upgrade from my Q7 when a version with better resolution screen and improved manual focus capability emerges (and settles down price-wise!). If it doesn't, I'll wait and pick up the discounted lenses / accessories I'd like but can't currently justify I came to the Q7 + lenses very late in the day at already-heavily-discounted prices, and that level of pricing is about right to me. I love the camera, but only based on what I paid for it!

10-28-2015, 07:06 PM - 1 Like   #122
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QuoteOriginally posted by Nicolas06 Quote
Sorry to say that you didn't get it. The crop factor of 3 is for the physical size of the sensor. It would apply if you were comparing a 12MP Q with a 12MP APSC. Or if we were speaking of a 24MP Q vs a 24MP APSC.

Now we were saying of the number of MP that remain if you go to Q framing with an APSC. This was say to be 2.6 MP. because well the APSC has 24. (24 / 3 * 3 = 2.66MP). This is direct application of this crop factor of 3 your speak of.
Up to this point you are correct.

QuoteOriginally posted by Nicolas06 Quote
Now in term of visible detail the Q is able to display 12MP while the APSC on the same surface has 12MP. In surface that a factor of 4.5 (4.8 when MP are rounded to 2.5MP only). There 4.5 time less pixels in the APSC than the Q from the same surface.
This section is arguing with your (correct) arithmetic in the earlier section. You correctly determined in the first section that in a rectangle of any given size, the APS-C sensor will have 1/9-th (not 1/4.5-th) the number of pixels that the same-MP Q sensor will have

QuoteOriginally posted by Nicolas06 Quote
If the pixel density is expressed not per surface area (2 dimension) but for a distance (like X pixels per mm and not X pixel per mm2), then you need to take the square root. This give you 2.12, Rounded to 2.2 coming from 2.5MP approximation.
This arithmetic is both unneeded and incorrect, because we already know that the Q sensor is 1/3-rd the linear dimensions of an APS-C sensor, so if each has the same number of pixels, the pixels on the Q sensor will be 1/3-rd as far apart as the pixels are on the APS-C sensor. Furthermore, your arithmetic is not relevant to your argument as you made it. Yes, pixels on a Q are closer together than they are on an APS-C camera, but I have never ever seen anyone use the word "crop" to describe that relationship; the correct term is "density", and its only relevance is that, as I have already mentioned, a lens designed for an APS-C camera may not resolve light down to the density of Q-7 sensor pixels.

QuoteOriginally posted by Nicolas06 Quote
So yes I should not have said crop factor because it confused you even if this is a crop factor. But because this term has already another meaning, the pixel density factor maybe would be a better term.

If you try to honestly follow what has been said still this doesn't change the reasoning and doesn't mean the Q got suddenly better because my naming convention what bad, the computation itself is valid.
Words have meaning - that is why we use them. When you use the wrong words, most likely you will convey the wrong meaning.
Mathematics has meaning - when you perform the wrong calculations, you cannot expect someone who knows the true calculations to be impressed.
And, in any case, you are still not addressing my original comments. When I originally posted those pictures, they were in response to your comments singing the praises of fixed lens cameras and cell phones. My point then remains, that for the same cost as a fixed lens camera, I can buy a Q which provides flexibility not available from any fixed lens camera. I never claimed that the birding picture I posted was the best birding picture ever taken - in fact I even included the disclaimer that this was taken with an older prime lens I was testing (and found wanting) in the hope that it would resolve better than the newer lenses I have (because in my experience, some older primes are much sharper than some newer zooms). Yes, I could put the same lens on my K-30 and then crop the result in PP. In that case, my view through the viewfinder leaves me guessing whether I got anything good or not; only when I get into gimp will I know anything. My personal experience was that this method resulted in poorer pictures than the Q is giving me. And the truth remains that my Q-7 is simultaneously giving me better birding pictures than I ever got before, and better pictures from a pocket camera than I have ever got before. I carefully studied cameras of all types before buying this Q-7, and I confidently claim that no fixed lens camera will do both of those things for me.

Last edited by reh321; 10-28-2015 at 09:28 PM.
10-28-2015, 10:00 PM   #123
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Great post reh321.
thanks
barondla
10-28-2015, 11:48 PM   #124
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Dear reh321,
I hate to add more off-topic posts to here, but I feel as if I need to do it once.

This APSC crop thing is about the only claim that was sort of interesting to me in Nicolas06's posts. His math is good for his claim. Yours is not.

That claim is that, when you (reh321) used 24MP APSC sensor interchangeable lens camera with the same lens as you used for your telephoto shot with Q7, the resulting image quality wouldn't be that different from what you get now as far as resolving power is concerned, and that one way to test it is to scale your image by a factor of 2.1 or 2.2. Therefore he made a 546x364 image out of your 1201x800 image.

If you genuinely do not understand his numbers, please have a look at this cartoon.

Even if you use your own numbers of 2000x1333pixels for cropped 24MP APS-C, the linear reduction factor from Q7 (4000x3000) image to cropped 24MP APS-C image that would give the same field of view as Q7 is somewhere between 2000/4000=1/2 and 1333/3000=1/2.251.

My response to Nicolas06 would probably be something like "doh, the image resolution cannot be better than the lens resolution, and there are better lenses, thanks for stating the obvious. And where can I buy 24MP BSI APSC ILC under 300USD with a kit lens?". Nevertheless, his math is legit. His math doesn't have anything to do with his use of confusing terminology.

It would be sort of interesting to ask if there are any lenses that would give you more resolving power with Q7 than with 24MP APS-C sensor, and if there are, which ones.

OK, I'm done. Now we can happily discuss if Q camera line is dead or not.

Best,
kwb

10-29-2015, 01:10 AM   #125
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I hope the Q is not dead!!! Love the camera (Q-7), although I would wish for slightly more DR & better high ISO... i don't want more MP, 12 is enough. A EVF wouldn't be bad either. Plus the Video stuff i mentioned before...
10-29-2015, 01:38 AM   #126
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its burning hot in here... if it would be dead it would be dead cold... but one flame hunts another in here... Despite that the Q System sells like hotcake in asian markets...

So i have to repeat:
I am pretty sure after FF production is up and running and maybe a second ff body(consumer grade like K-50) has hit the market, we will see a new Q with EVF built-in or optional.
10-29-2015, 01:46 AM   #127
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QuoteOriginally posted by kwb Quote
My response to Nicolas06 would probably be something like "doh, the image resolution cannot be better than the lens resolution, and there are better lenses, thanks for stating the obvious. And where can I buy 24MP BSI APSC ILC under 300USD with a kit lens?". Nevertheless, his math is legit. His math doesn't have anything to do with his use of confusing terminology.

It would be sort of interesting to ask if there are any lenses that would give you more resolving power with Q7 than with 24MP APS-C sensor, and if there are, which ones.

OK, I'm done. Now we can happily discuss if Q camera line is dead or not.

Best,
kwb
The issue with the theory that you get more with you Q due to higher pixel density is that the lense that are good enough for that are more in the 16mm-135mm range than in the 200mm-600mm range. Oh maybe we could try the DA560, but the price is to take into consideration. If we look at DxO resolutions figures even a DA*300 is visibly less sharp than a DA35 macro on a K3 or K5-II meaning we are already facing the limits of DA*300 with a 24MP sensor. Sure a TC give a bit more, but apparently it is not at good as the 150-450 @ 420mm. 24MP maybe doesn't outresolve the DA*300 fully, but we are not far.

So yes, take a 100mm macro f/2.8, put it on a Q and get 2.1 time more details on the Q than K3. The framing would be like a 300mm lens. and the setup would be smaller than what you'd need on your DSLR. Not with an old 300mm prime full of CA.

10-29-2015, 02:52 AM   #128
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the FA 50mm 1.4 will also do very well once stopped down i guess... i dont know about the absolute optical resolution of the "Tamron 70-200 2.8" but i am pretty sure it could do wonders on Q7/Q-S1... or maybe some Angenieux lens that was originally for 16mm film format... (a bit costy -hehe..)

But maybe we will see a dedicated super-Tele Lens for the Q in the future... who knows?
10-29-2015, 03:38 AM   #129
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QuoteOriginally posted by Nicolas06 Quote
The issue with the theory that you get more with you Q due to higher pixel density is that the lense that are good enough for that are more in the 16mm-135mm range than in the 200mm-600mm range. Oh maybe we could try the DA560, but the price is to take into consideration. If we look at DxO resolutions figures even a DA*300 is visibly less sharp than a DA35 macro on a K3 or K5-II meaning we are already facing the limits of DA*300 with a 24MP sensor. Sure a TC give a bit more, but apparently it is not at good as the 150-450 @ 420mm. 24MP maybe doesn't outresolve the DA*300 fully, but we are not far.

So yes, take a 100mm macro f/2.8, put it on a Q and get 2.1 time more details on the Q than K3. The framing would be like a 300mm lens. and the setup would be smaller than what you'd need on your DSLR. Not with an old 300mm prime full of CA.
Hi Nicolas, promises, promises. Yesterday you said "Sorry for the incoveniance, I'll stop there."...
Now I'm no longer sure what your argument is. There is a long running thread "Reach of the Q" here that shows the DA*300 to be a stunning performer on the Q. Anyway, as you won't stop, I'll challenge you. Show me better with an APS-C Pentax and lens of your choice. (And please include price of the kit) than what I have here with a Q10 and an old Canon Fd 200mm f/4.0 (cost roughly €300,-). And mind you, the limits of resolution visible are atmospherically induced as I took this picture in Germany and not the Mojave desert.
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10-29-2015, 03:39 AM   #130
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QuoteOriginally posted by monochrome Quote
Go away. This is our Forum.
Are you taking to me?
10-29-2015, 03:42 AM   #131
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QuoteOriginally posted by patarok Quote
the FA 50mm 1.4 will also do very well once stopped down i guess... i dont know about the absolute optical resolution of the "Tamron 70-200 2.8" but i am pretty sure it could do wonders on Q7/Q-S1... or maybe some Angenieux lens that was originally for 16mm film format... (a bit costy -hehe..)

But maybe we will see a dedicated super-Tele Lens for the Q in the future... who knows?
Yes please, a super-zoom like any manufacturer (incl. Pentax) has for their bridge cameras would be very nice indeed.
10-29-2015, 07:01 AM   #132
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This all just seems like a fancy way of saying the Q7 has smaller sensor sites. But that's not a good thing. Smaller sensor sites are less sensitive and subject to (relatively) more noise than large ones. That's why the Q7 has poorer high-ISO performance than cameras with larger sensors.

Although, I suppose the noise does contribute to the "film-like" look of Q7 images that some have commented on. It looks like film grain.

Last edited by Tony Belding; 10-29-2015 at 07:02 AM. Reason: remove quotes
10-29-2015, 07:58 AM   #133
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QuoteOriginally posted by eyeswideshut Quote
Yes please, a super-zoom like any manufacturer (incl. Pentax) has for their bridge cameras would be very nice indeed.
why don't you simply buy a superzoom, they already exist, with EVF and larger grip, with 1/2.3", 1/1.7", 1/1.5", 1" sensors etc...
10-29-2015, 08:12 AM   #134
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QuoteOriginally posted by alliumnsk Quote
why don't you simply buy a superzoom, they already exist, with EVF and larger grip, with 1/2.3", 1/1.7", 1/1.5", 1" sensors etc...
Why buy another camera when you already have an ILC? A nice wide angle prime would be nice too.
10-29-2015, 08:36 AM - 4 Likes   #135
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People keep trying to make rational arguments from the perspective of a large-format dSLR or MILC. They don't seem to understand that final absolute IQ is not the primary objective; ranking Q by that standard completely misses the point.

Please stop trying to 'nudge' me to make the decision that you 'know' is in my best interest. You and I do not agree on the feature ranking weights, so your conclusion of my best interest is plain wrong - but that's a common complaint these days.

I tire of being told someone understands my best interest better than I do and that I am too stupid or poorly educated or unsophisticated to make good decisions, so 'said someone' will make my 'good' decisions for me.

Q does precisely what I bought it to do. I have other cameras that do precisely what I bought them to do. OK?
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