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12-26-2014, 04:59 PM   #16
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I don't think they do, come to think of it. The construction is pretty similar to the Toy lenses but it just says something like "03 Fish-Eye Lens" on it. I've yet to have a chance to do more than close-up cat photos with mine yet as the weather has been pants here for the past couple of days.

The 04 and 05 still aren't as toy-like as the name would suggest though, looking at sample images.

12-26-2014, 06:27 PM   #17
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QuoteOriginally posted by Dangermouse Quote
I don't think they do, come to think of it. The construction is pretty similar to the Toy lenses but it just says something like "03 Fish-Eye Lens" on it. I've yet to have a chance to do more than close-up cat photos with mine yet as the weather has been pants here for the past couple of days.

The 04 and 05 still aren't as toy-like as the name would suggest though, looking at sample images.
I think you'll see that the 03 is a useful little lens once you get out and about with it. Between the 01, 03, and 06 I have a great time with my Qs (I have the 02 but its just not in the league with the others IMHO).
12-26-2014, 08:14 PM   #18
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QuoteOriginally posted by Nicolas06 Quote
But then, how it is especially incredible? f/2.8 just mean that the 45mm focal length has an apperture of 16mm diameter... There nothing magical in this f/2.8 number... On the 207mm equivalent, this would have to be 74mm. That why such lense is big... Even through the light density doesn't change, the total light that goes on the sensor change... And with it noise levels.
I've had my Q7 for just a week so far, but I've found the noise levels to very acceptable.The mathematics of lens specs is immaterial - the neat part is getting good pictures from such a small/light system.
12-26-2014, 08:16 PM   #19
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QuoteOriginally posted by Nicolas06 Quote
But then, how it is especially incredible? f/2.8 just mean that the 45mm focal length has an apperture of 16mm diameter... There nothing magical in this f/2.8 number... On the 207mm equivalent, this would have to be 74mm. That why such lense is big... Even through the light density doesn't change, the total light that goes on the sensor change... And with it noise levels.
It is especially incredible.........for what it is, because I know of nothing else like it, an interchangeable 207 mm f2.8 equivalent lens that one can easily fit into a pocket of light weight shorts. I know that it is not bending the laws of physics and you have yet to tell me something I don't already know. Just for the record though, you win. Feel better?

12-27-2014, 06:12 AM   #20
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QuoteOriginally posted by mepaca Quote
It is especially incredible.........for what it is, because I know of nothing else like it, an interchangeable 207 mm f2.8 equivalent lens that one can easily fit into a pocket of light weight shorts. I know that it is not bending the laws of physics and you have yet to tell me something I don't already know. Just for the record though, you win. Feel better?
I'm not Nicolas, but I don't particularly feel better from you claiming both that he won and that you know, and in the same post you still claim that it's equivalent to a longer f/2.8 lens. It just isn't. No way. It is an f/2.8 lens, certainly, but if you scale one thing for equivalence you have to scale the other too. Or you can talk just about equivalent angle of view, but that looks like you're still trying to mislead. (Mislead yourself probably.) The lens doesn't need to be equivalent to something it isn't equivalent to, it's still a fine lens as it is. Which is a slow but very small and light tele.

And also for the record, in case you really do know: Others don't. Please don't mislead them by making incorrect statements.
12-27-2014, 06:38 AM   #21
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QuoteOriginally posted by drougge Quote
I'm not Nicolas, but I don't particularly feel better from you claiming both that he won and that you know, and in the same post you still claim that it's equivalent to a longer f/2.8 lens. It just isn't. No way. It is an f/2.8 lens, certainly, but if you scale one thing for equivalence you have to scale the other too. Or you can talk just about equivalent angle of view, but that looks like you're still trying to mislead. (Mislead yourself probably.) The lens doesn't need to be equivalent to something it isn't equivalent to, it's still a fine lens as it is. Which is a slow but very small and light tele.

And also for the record, in case you really do know: Others don't. Please don't mislead them by making incorrect statements.
Ok, well let me rephrase that - a 207mm equivalent f2.8 lens.
12-27-2014, 07:11 AM   #22
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QuoteOriginally posted by mepaca Quote
Ok, well let me rephrase that - a 207mm equivalent f2.8 lens.
a 207mm equivalent f/13 lens. That all it is about. You said you did understood isn't it ? So why do you continue to use the wrong equivalence numbers?

This is not to say this tele is no good. I have nothing against it. This is conveniant and in good light you get nices shoots. That the whole point isn't it ? But you know all smartphone have f/2.5 or wide apperture prime now. Their lenses are few mm wide. Many compact also have f/2-f/2.8 zooms lens now. f/2.8 is pretty standard for such sensor size.

This is not bad or good, and for sure f/2.8 still allow for shallower deph of field and more light than f/5.6... This is all valid while you keep a given sensor.

But from practical point of view, if you take 2 shoots with same framing at 200mm (FF framing), one with the Q-S1 the other one with an FF, both at f/2.8:
- the deph of field will be dramatically different.
- iso setting will be the same for both... Meaning the FF will offer much better quality... Same at iso 2000 on FF than at iso100 on Q-S1.

Anybody looking at the 2 image will immediately spot the difference. First of deph of field at low isos setting, second of noise at high isos setting. While if you set f/13 on the FF lense... Well it will look the same.

I insist because some people might think for example that their 55-300 f/3.5-5.6 might be not as suitable as f/2.8 Q-S1 lense due to the f/5.6 only while it is obviously wrong. Another example. DA70 ltd is not that big. Still put it on K3, shoot at f/4, crop to 50% size and you get equivalent of 210mm FF framing f/11 6MP shoot... Half the pixels that what you would get Q-S1 45mm @ f/2.8, but still 0.5EV more for noise performance. And the lense isn't that big.

Last edited by Nicolas06; 12-27-2014 at 07:55 AM.
12-27-2014, 08:17 AM - 1 Like   #23
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QuoteOriginally posted by Nicolas06 Quote
a 207mm equivalent f/13 lens. That all it is about. You said you did understood isn't it ? So why do you continue to use the wrong equivalence numbers?

This is not to say this tele is no good. I have nothing against it. This is conveniant and in good light you get nices shoots. That the whole point isn't it ? But you know all smartphone have f/2.5 or wide apperture prime now. Their lenses are few mm wide. Many compact also have f/2-f/2.8 zooms lens now. f/2.8 is pretty standard for such sensor size.

This is not bad or good, and for sure f/2.8 still allow for shallower deph of field and more light than f/5.6... This is all valid while you keep a given sensor.

But from practical point of view, if you take 2 shoots with same framing at 200mm (FF framing), one with the Q-S1 the other one with an FF, both at f/2.8:
- the deph of field will be dramatically different.
- iso setting will be the same for both... Meaning the FF will offer much better quality... Same at iso 2000 on FF than at iso100 on Q-S1.

Anybody looking at the 2 image will immediately spot the difference. First of deph of field at low isos setting, second of noise at high isos setting. While if you set f/13 on the FF lense... Well it will look the same.

I insist because some people might think for example that their 55-300 f/3.5-5.6 might be not as suitable as f/2.8 Q-S1 lense due to the f/5.6 only while it is obviously wrong. Another example. DA70 ltd is not that big. Still put it on K3, shoot at f/4, crop to 50% size and you get equivalent of 210mm FF framing f/8 6MP shoot... Half the pixels that what you would get Q-S1 45mm @ f/2.8, but still 1.5EV more for noise performance. And the lense isn't that big.
For the criteria I use ie. focal length and f stop (focal ratio) they are equivalent. The angle of acceptance is the same and the focal ratio is the same. The focal ratio of f13 that you suggest is absolutely not the same and at the same shutter speed would result in a much darker photograph. That is hardly equivalent. You seem to be confusing focal ratio with depth of field.

12-27-2014, 08:56 AM - 1 Like   #24
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QuoteOriginally posted by mepaca Quote
For the criteria I use ie. focal length and f stop (focal ratio) they are equivalent. The angle of acceptance is the same and the focal ratio is the same. The focal ratio of f13 that you suggest is absolutely not the same and at the same shutter speed would result in a much darker photograph. That is hardly equivalent. You seem to be confusing focal ratio with depth of field.
As I said, scale all the numbers, or none of them.

You are shooting a 45mm lens at f/2.8 on a Q7 sensor at ISO 100.

You could equivalently be shooting a 210mm lens at f/13 on an FF sensor at ISO 2000. (All numbers rounded.)

Assuming that transmission through the lenses matches (same t-stop) and the sensors are lying the same amount about their ISO, you will get the same brightness on those photos at the same exposure times.

There is little reason to do this, but if you want to know what some system you aren't using would contain, this is how. Scaling some parts of the system while leaving other parts unchanged is not how. It gives you nonsense results.
12-27-2014, 09:53 AM - 1 Like   #25
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We all know what mepaca meant, and he/she knows what you all mean.

Done.
12-27-2014, 09:58 AM   #26
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Too bad none of the manufacturers don't use Total Light Gathering in their specifications. Now I can take my pinhole 14X17 camera to shoot sports because in converting it's TLG it is now much faster.

The Q lens is a 2.8 no matter what system you compare it to in terms of how much light it needs to capture an image. The focal length equivalency is just a method to allow people to have some understanding of which is a wide angle and how long is the telephoto one. I certainly would walk out of any camera store that brought up all this Total Light stuff. It is meaningless to practically everyone on this planet. Smaller sensor the noisier the image is all most of us need to know.

still it is nice to know that every camera and lens manufacturer is talking nonsense.
12-27-2014, 11:11 AM   #27
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QuoteOriginally posted by filoxophy Quote
We all know what mepaca meant, and he/she knows what you all mean.

Done.
Thanks man
12-27-2014, 12:07 PM   #28
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The argument that equivalent apperture is not important is to think that to keep the same iso, a pure technical parameter, is more important than to keep the deph of field you wanted, the control on movement you wanted and the perspective you wanted.

Kind of the f/2.8 was used just to get the right exposure... One could have choosed f/5.6 or f/8 exactly the same... He didn't care.

This is true for some shoots where the apperture is not that important and one should choose the one that give the best quality overall (so likely f/4 or f/5.6) or if there no much light, a large apperture one to avoid having too high isos or too slow speed.

For other cases, this doesn't make much sense.

Last edited by Nicolas06; 12-27-2014 at 12:14 PM.
12-27-2014, 03:00 PM   #29
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QuoteOriginally posted by monochrome Quote
The 06 is sharp, bright and contrasty for such a tiny zoom lens. Given the quality of all the others I can't understand why the 02 is a (comarative) slouch.
And why oh why is the 02 such a nicely built lens and the 06 feels like it was made by the lowest bidder?

Lee

---------- Post added 12-27-14 at 05:19 PM ----------

QuoteOriginally posted by mepaca Quote
Thanks man
I don't know about anyone else, but I'm sure not going to call the 06 incredible around here. I hope it is okay to call it most excellent...

Lee
12-27-2014, 08:47 PM   #30
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Fstop of the lens is a fixed number arrived at by measuring the focal length and the aperture size. It doesn't change with the sensor size. If I put a 45mm 2.8 lens on the Q I would get roughly the same field of view as the 06 lens. And if I could adapt the Q 06 lens to the K3 it would be like a 45mm except it wouldn't cover the sensor. Or I could crop a shot made with a 45mm 2.8 lens on the K3 down to the size of the Q sensor to get an equivalent field of view. The f stops of the lens don't change. They are fixed in hardware. The equivalency numbers represent the field of view.

That is pretty impressive for such a small body. I was disappointed with the iq of the original Q, and have been eyeing the Q7 or later for improvements.
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