[charlesdanb]

Hi everybody, I have a question about manual focus K mount lenses. I've been shooting with a K1000 for about a year now (my first camera) paired with the SMC Pentax M 1:2 50mm that came with it. I do some picture taking indoors and was wondering if it would be worth getting an f/1.4 50mm. How much of a difference do those extra stops make in indoor photography?

Alternatively, are there other lenses (telephoto?) that would be a better investment? I'm not a serious photographer in any sense, just want to document my life in a semiartistic way.

Thanks for your help!

[troika]

The extra stop absolutely makes a difference.

There are 3 elements that control exposure:

1) Your film speed. With film photography, you can't change this to get the shot, whatever you buy is what you have. If you haven't noticed this, film is (almost always) sold in 1 stop incriments. 100, 200, 400, 800, 1600.

2) Shutter speed. Indicated on your dial in full incriments (I think. I don't have a K1000 anymore). When photographing still objects, hand held, the denominator in your shutter speed should not be lower than your focal length, so in your case 1/60th of a second. If you have a steady hand or brace yourself/your camera, you might cheat this a stop.

3) Aperture. On your lens.

1 stop of any of those elements is equal to one stop of any of those other elements.

If you're taking a photo at 1/60s with 100 speed film at f2.8, it is the same as 1/60s with 200 speed filmand f4 -or- 1/30s at 100 & f4

F1.4 is a stop faster than f2 if you're missing that shot, but you could also use faster film indoors.

If the object you're photographing is moving, the shutter speed can't keep going down to get your exposure or the subject will blur.

1.7, 1.8, and 1.4 lenses might be better quality and you may enjoy having one, but it's just one part of the equation. If you're shooting slower film, it would be cheaper to fix it there.

As for other lenses, consider something wider, like a 28/2.8. That can be a good focal length indoors and though it is a stop slower, you can hand-hold at 1/30s, which gives you that stop back. There are about a billion used 28mm lenses out there that would be great for your camera.

There are also flashes, but I assume you don't want to go there.

[pepperberry farm]

there's also the A50/1.2 and several 55/1.2 lenses out there...

[pschlute]

I do some picture taking indoors and was wondering if it would be worth getting an f/1.4 50mm. How much of a difference do those extra stops make in indoor photography?

The difference between f2 and f1.4 is 1 stop. As detailed above this means you can use one stop faster shutter speed to capture your image....so 1/60 instead of 1/30 for example. BUT...... it very much depends on what you are photographing as to whether this will help you. A f2 lens at 10 feet has a DOF of only 1.5 feet. A f1.4 lens will will have a DOF of only 1 foot. If your "indoors" is in poor light you will have difficulty focussing accurately, and more so with a 1.4 lens. Without more detail I would suggest investing in a flash system would give you greater flexibility than a 1 stop increase in light gathering from a lens.

[aslyfox]

i wonder if the OP has seen these charts yet:

Pentax K-Mount Lens Series Explained: The differences between various Pentax lens series

In a nutshell
There are several series of Pentax K-mount lenses; the ones currently being produced include the DA (digital), DA L (cheap digital kit), D FA (full-frame, digital optimized), and FA (full-frame) series. While all Pentax K-mount lenses ever produced are compatible with all current Pentax DSLRs (in some cases with restrictions in that not all exposure modes of the camera are supported by old lenses), there are significant differences between each lens series and each has different features. Furthermore some of the newer lenses do not work with older cameras. We'll be exploring the differences between the various K-mount series lenses in this article.

Pentax K-Mount Lenses Explained: The differences between various Pentax lens series

Pentax Lens Compatibility Chart
Copyright 2006-2018 Mosphotos.com. All rights reserved.

Pentax bayonet lenses labeled "SMC Pentax" are referred to as "K" lenses in the table below. Other Pentax bayonet lenses have the lens designation as a part of their name as in "SMC Pentax-FA".
Note that "star" lenses work like their "non-star" counterparts unless they are singled out in the table below. So for compatibility of a DA* lens, look under DA lenses, etc.
Exceptions:
FA and F "soft" lenses behave like M lenses in terms of metering.

The Pentax Camera Lens Compatibility Chart

[ismaelg]

Hello,

The 1.4 will make a difference. Keep in mind at those wide apertures, depth of field becomes a factor to consider. It can be used to your advantage but it can also be a challenge to control.
How about exploring other focal lengths? For indoors, a 28mm lens can be very useful.
For telephoto, my favorite manual zoom is the Pentax A70-210 f4. Very sharp, great build quality and still affordable.

Thanks,

[dms]

The quality of the f/2 50mm is generally considered to be fine, and in fact for close up photography (w/ teleconverter or diopter lens or extension tubes) it is probably as good as you can get short of getting a macro lens. Only you know if the 1 stop** difference is important--but likely not. But using f/1.4 or f/2 on the faster lens may make the out of focus areas look different/better (bokeh) but since you don't mention this it likely is not a consideration at this point. Usually buying a "better" lens or "better" dslr does very little compared to better technique and better post processing the images.
___
**My bad, should be 1 stop.

---

Last edited by dms; 07-27-2020 at 05:03 PM.

[charlesdanb]

Thanks everyone for your responses—this gives me a lot to chew on. What a wealth of understanding on this forum! I'll be sure to check out all the lenses y'all recommend. I particularly like the idea of trying a 28mm.

Not sure what y'all consider good topic etiquette around here, but a few more questions have occurred to me unrelated to lenses. I wonder if I can ask them without starting a new thread.

1) troika mentions flash. I have a flash (Vivitar?) with a hinge for angling up and down. Haven't used it yet since I just got my hot shoe repaired by Mr. Hendrickson. Have any of you had any success "bouncing" the flash for more natural lighting, or should I avoid flash altogether in low light?

2) troika also mentions high speed film. I have done a little research into Delta 3200 and T Max P3200, and I'm having a difficult time wrapping my head around a film with nominal sensitivity 3200 ISO, but the actual sensitivity is lower, and the film can be successfully shot at different ISO settings and developed for different amounts of time. Please excuse my "amateurity." I guess what I want to know is, can I shoot and develop at 3200 ISO, as it says on the box, without getting into anything more complicated, with good results?

[garywakeling]

Hi , bouncing the flash can give a nicer , more natural feel to your photos, youtube has many videos showing the how to, just a warning that low white ceilings work well, dark or coloured ceilings can give some interesting results . OK as long as you know the effect. Shooting and bouncing of the wall or cards can work well too.
The film can easily work at 3200 ISO without any bother
Enjoy you camera and remember for years the classic 35mm film kit was a 28 or 35mm lens, a 50mm standard and a 135mm telephoto. Plenty of great images made with that combo

[pschlute]

or should I avoid flash altogether in low light?

The answer entirely depends on what you photograph, under what existing ambient light, and at what distance. This should help us narrow down your answer

[TomB_tx]

I’ve been shooting indoors “available light” without flash for over 50 years. While I’ve had f1.4 and f1.2 lenses, I have preferred the results with an f2.0 to f1.7 lens, and have used these most of the time, normally with 400 speed film. (Although in the 1960s often used a special developer to give TriX an effective 1200 speed for indoor sports.) I find that even stopped down to f2 the Pentax 50 f1.4 K mount lens has less even sharpness across the field than the slower lenses at the same aperture. The larger, fast lenses look more impressive on the camera, if that is important to you. I think the 50 f1.7 SMC M lens is the best performing Pentax 50 of that time period.
These days for digital I use a $6K Leica camera usually with f2.5 50 & 35mm lenses, in spite of owning more expensive f1.4 lenses in both focal lengths. I prefer the smaller size of the slower lenses, and the image quality can’t be beat.
It is harder to correct optical aberrations in faster lenses.

[ramseybuckeye]

Before buying into too many lenses think about what you have been shooting and what can make it better. But if you see a good deal on that 50/1.4 grab it before it is gone. The most plentiful manual lenses out there are the 50s, 28s, 135s, and then maybe 35s. Most of those can be found pretty easily, often at some attractive prices.

[Astro-Baby]

Its hard to advise without knowing what the subject is....if you are self portraiting yourself I am guessing a tripod might be in use so a slower shutter speed isn’t neccessarily a problem. Depends what you are doing in front if the lens but a bit of motion blur can help tell a story.
There are no imperatives and all the rules can be broken if needs be.

Personally I never found that extra stop to be useful enough to make me want to pay the huge premium for a faster lens and I did at one time own an f1.2 Zuiko and even now have some f1.4s. The reason for owning them now is not to gain an extra stop of performance for low light but to create shallow depths of field and exploit the bokeh ( plus one of them just happens to be a lovely lens in its build quality etc ). For indoor self portrait type work I would invest in a flash, and diffuser. Bounce flash for a more gentle, less stark look is easy enough with a little practice and there are plenty of online guides. Ditto fill in flash.

Rather than gain a single stop with an expensive lens you could, as mentioned, just bump the film speed up a notch.

[Papa_Joe]

Could you please give us some more information about what your main subject is and where you are mostly shooting?
What type of film are you using mainly? Do you develop it by yourself? Do you keep your pictures as prints or as


If you are doing indoor photography mainly, I would suggest a wide angle 35 mm or 28 mm lens. You can get the M 28 mm 2.8 quite cheap. And 2.8 it is fully usable indoors. I would prefer a 35 mm for reporting style photography, but you have to test that by yourself. If you are really sure about the focal lenght you can try to get a 35 mm 2.0. A great available light lens, but a bit expensive (around EUR 200,00).

Concerning a telephoto. If you are not using it mainly indoors in low light, I would suggest a tele zoom.


My suggestion would be, try to get some affordable lenses of the M series to test which focal lenght serves you well, and then search for something more expensive. I bought a M 2.8/28, a M 3.5/135, a M 4.0/75-150 (a good lens as well) and a M 4.0/200 during the last two years. All in near mint condition, none over 40 EUR. I guess the american market is in the same price range.

[Lord Lucan]

I have a flash (Vivitar?) with a hinge for angling up and down. ....Have any of you had any success "bouncing" the flash for more natural lighting, or should I avoid flash altogether in low light?

I always use bounce flash off the ceiling indoors for more even and softer lighting, but you need a reasonably powerful flash unit to do it, say a Guide Number of around 30* or more. You don't say what Vivitar unit you have, but I guess if it tilts it will be fairly powerful. You would only not use flash in low light indoors if you were deliberately after a moody effect.

* That is 30 in metres at ISO 100 film speed.