Working in low light. Suggestions?

delegopa · 02-19-2014, 08:20 AM

Hello folks,

When being with families and friends in low light but nice ambient , I like to capture the mood and go for candids. A flash as well as screw drive will usually kill this by alerting them before my shot. Thus I try to work with fast lenses instead. Problem so far: Only got a Ricoh 50mm f2 for this approach, which is MF. I practiced a good bit to nail the focus. But this only works for me when light is not too dim.
Recently we were in a very dim bar. I got some acceptable shots where lots of small lights/candles around really boosted the mood.But there were also a lot of misfocussed shots. I found it really hard to get the focus right via the viewfinder, the AF notice was often to slow to help either. I shot at ISO 1000 | 1600 and shutter 1/15 to 1/25 (SR rocks) at f2. Later i went for f2.8 and ISO 2500 to get more DOF but the noise killed the details then. Always underexposed about one stop.

I think that a split prism like in the analog SLR i got could help, but I dont want to modify my K-30 internally.
Any hint how to approach such a situation next time? How would a AF lens perform in these conditions? (The yet to be available Sigma 30mm f1.4 Art looks promising to me)

Thanks for reading.

VoiceOfReason · 02-19-2014, 08:43 AM

You may also try llive view and focus peaking with the MF lenses. That should help with focus, and use spot metering, Av, and lock your ISO to try to keep from underexposing.

**rbefly** · 02-19-2014, 08:51 AM

Hello delegopa,
Available-light shooting is tricky under any conditions, and worse in very low light. Some A/F systems (mostly the in-camera detection) are better than others, but they all have problems. Pentax isn't a leader in that area, but the K-30 is fairly new and should be decent.
Overall, I like M/F lenses in low light situations.
But even the best M/F lens/body combination will still be limited by the viewfinder screen, and that can easily be upgraded. For about the price of a good M/F lens ($100 USD) a focusingscreen.com or Katzeye split-prism will make a major difference.
They're not hard to install and it only takes a few minutes. From then on, your M/F accuracy and 'keeper' rate will go way up and your right eye will thank you. Indoors I usually use an eyecup (rubber eyepiece) to keep side distractions to a minimum. This also works great in overly-bright outdoor light.
Or, an OEM53 magnifying eyepiece helps too, they're about $25 or so.
A small tabletop tripod or beanbag is handy and portable.
If you try the upgraded screen and a couple of fast legacy M/F primes, I'll bet you have better luck! There's also a few Sigma and Samyang fast primes available new.
JMO,
Ron

asp1880 · 02-19-2014, 08:56 AM

"focus bracketing" can also work. I sometimes put the camera in highspeed drive mode and shoot bursts while tweaking the focus ring. I delete lots but also get some sharp ones.

Regards,
--Anders.

**sholtzma** · 02-19-2014, 09:12 AM

When you say "noise killed the details", what are you saying? Did you use noise reduction effectively in post-processing but lost crucial details? Did you not use noise reduction (or not effectively) and found that the noise itself obscured details? Was it noise that obscured details or was it movement due to slow shutter speeds? How high an ISO can the K-30 go to with acceptable noise that can be dealt with in a good noise reduction program? Do you have such a program?

Just a few questions whose answers would help guide people's responses to your understandable concerns about low-light shooting....

wildman · 02-19-2014, 09:58 AM

Originally posted by sholtzma

When you say "noise killed the details", what are you saying?

I was thinking along the same lines.
Good PP technique can easily add 1-2 stops to your max effective aperture without the addition of any hardware if used effectively.

K5, Cheapo Sigma 70-300mm Zoom at f/8, ISO 6400, 1/200, at 70mm and this is off a jpg not RAW.

narual · 02-19-2014, 10:13 AM

If you don't mind going a little wider for easier depth of field, get a cheap 28mm 2.8 manual lens (I paid $5 for mine at my local camera store), focus to the appropriate distance using the markings on the lens, and as long as no one moves more than a couple feet, you're fine.
Focus 10 feet away at 2.8, and everyone between about 8 and about 13 feet from you will be in focus. Bump it to f4 and you get from about 7.5 to about 14.5 feet, which would cover an entire table at a restaurant or bar pretty well.

Online Depth of Field Calculator

A better focusing screen is only going to be really helpful if you're going faster than f/2-2.5, and in poor lighting, it's going to be harder to see. Definitely get one if you think you'll be delving into manually focusing f/1.4 or f/1.2 lenses though!

And the screw drive isn't really that loud. You're holding the camera so you'll notice it, but the sound doesn't travel much unless you're in a quiet room and no one is talking.

flyer · 02-19-2014, 10:42 AM

You could also try catch in focus. As you move the focus ring, as soon as the focus is reached, the shutter will activate.

monoloco · 02-19-2014, 12:15 PM

Originally posted by narual

If you don't mind going a little wider for easier depth of field, get a cheap 28mm 2.8 manual lens (I paid $5 for mine at my local camera store), focus to the appropriate distance using the markings on the lens, and as long as no one moves more than a couple feet, you're fine.
Focus 10 feet away at 2.8, and everyone between about 8 and about 13 feet from you will be in focus. Bump it to f4 and you get from about 7.5 to about 14.5 feet, which would cover an entire table at a restaurant or bar pretty well.

.

I wish that they would have provided distance markings on the 18-135 WR because that is my preferred method.

delegopa · 02-20-2014, 05:06 AM

Thanks to everyone for all the feedback!

Trying to reply to all this helpfull input:

I find that focus peaking is a lot easier then using the viewfinder. But usually i just forget its there... could make steady shots harder too. Let's see if I remember it next time

This was maybe misleading, but I underexposed on purpose(higher shutter speed / lower ISO). Indoors I usually set the exposure up once and tweak if needed.

Got some AF Lenses too and use the center AF point and compose after focus. Heard split-prisms can influence this and also read that some calibration of the new screen could be needed. If i had a second body I would do it in an instant...

Actually i got some practice last evening when I met with friends again. Took my small tripod with me, which is barely able to hold the cam with the small prime, and left it in my jacket

We sat around a low table all the time so it would not have helped much this time.

Focus bracketing could be useful if the shot is critical for me. Have to try this.

On the noise questions:
Most of my pictures are processed in lightroom only. I rarely use the in-built noise reduction. However I reviewed my shots in the bar again and came to the conclusion that sharpness was mainly lost by mediocre focus and camera shake.
With this in mind I boosted the ISO to 2500 right from the start last evening. Got some nice captures and the noise is no issue in them. It was not that dim this time so focusing was easier. But still some shots OOF.

Definitly want to go wider so I get more options in composition too. Will give ebay a visit soon. K-Mount indeed helps working with a small budget

The lenses I got from my grandfather are sadly all in fujica x-mount. Konverted a 28mm but this can only focus close now. One of them is a 50mm f1.2 sitting on a analog body and waiting to be used again...

The screw drive I got are a Sigma 70-300 and the F 35-80 and I find them relatively loud. Will look into this again when I find a screw driven lens that is bright enough to use in the described situation.

The problem with catch in focus was for me that it takes a bit of time in low light. This would be my preferred method elsewise.

ablahblah · 03-05-2014, 02:10 AM

Wanted to chime in and say I'm interested too, I have a Ricoh 50mm F2 as well that practically saved my butt at a conference event. All my other lenses hit above F4, and my M4/3 system shot them all down with ISO noise. I found it hard to consistently nail the focus on the Ricoh at F2 though!

One thing I noticed is that you said you were shooting at 1/15 and 1/25? I usually try to shoot at a minimum shutter speed that is reciprocal of the focal length so camera shake doesn't mess up my shots.
A wider lens would help for sure with focus and letting you hit a lower shutter speed without camera shake.

derekkite · 03-08-2014, 10:42 PM

Originally posted by delegopa

Hello folks,

When being with families and friends in low light but nice ambient , I like to capture the mood and go for candids. A flash as well as screw drive will usually kill this by alerting them before my shot. Thus I try to work with fast lenses instead. Problem so far: Only got a Ricoh 50mm f2 for this approach, which is MF. I practiced a good bit to nail the focus. But this only works for me when light is not too dim.
Recently we were in a very dim bar. I got some acceptable shots where lots of small lights/candles around really boosted the mood.But there were also a lot of misfocussed shots. I found it really hard to get the focus right via the viewfinder, the AF notice was often to slow to help either. I shot at ISO 1000 | 1600 and shutter 1/15 to 1/25 (SR rocks) at f2. Later i went for f2.8 and ISO 2500 to get more DOF but the noise killed the details then. Always underexposed about one stop.

I think that a split prism like in the analog SLR i got could help, but I dont want to modify my K-30 internally.
Any hint how to approach such a situation next time? How would a AF lens perform in these conditions? (The yet to be available Sigma 30mm f1.4 Art looks promising to me)

Thanks for reading.

Prism viewfinders will go black in low light. Manual focus is a motor skill that is learned by repetition. Take lots of shots in low light and over time you will get more keepers. Just remember that it is a tough challenge; if there is little contrast to see, getting focus is difficult.

delegopa · 03-09-2014, 03:46 AM

Thanks again, at least this training can be fun

But in low-light it can get a bit straining.
Those shutter speeds definitely weren't perfect but usually I can hold the camera steady enough that shake reduction can do the rest. But it sometimes happens that I forget to steady.

The focussing is the main issue for me. In most of the bad pictures you can easily see the focussed plane is somewhere else then intended. Somewhere in these forums I read about the viewfinder representing DOF like it was about f4 (when the lens is f4 or faster).
Anyway i have to practice more, maybe i will get something nice to share then.

rawr · 03-09-2014, 06:52 AM

My 2c:

I would go to ISO 3200 or even 5000 on the K-30. Those ISO's should be capable of giving acceptable image quality results, especially if you use Lightroom (as you already do).

If higher ISO lets you hold a higher shutter speed and get less blur, that will be a positive outcome. Noise is relatively easy to clean up, but motion blur often simply means 'delete'. I'd rather have a sharp but noisy image over a noise-free but blurry picture any day.

You may also find that if you run the ISO a little higher into those high ranges, you may be able to run the aperture one-notch higher in very low-light (eg from f2 to f2.8), which in turn could give you a whisker more DOF, whilst still holding onto a decent shutter speed, and so help you get a sharp shot.

I also hope you aren't using any filters on your len (UV or 'protection'). If yes, I'd remove any filters. They can make the lens darker, and due to stuff like flare and distortion, may also impact the optical quality of the lens, which may make your AF sensor (and hence your green hexagon) a little less accurate too. I'd also recommend using a hood, even indoors and in low-light. It will increase contrast and reduce flare, which may perhaps make focussing easier for you.

Another simple thing I do when shooting in dark venues is to turn off all the camera lights - especially the rear LCD, but also anything else that blinks. It helps your eyes adjust to low-light. And don't chimp after every shot. Shoot a set, then chimp. Or just save all your chimping until you get home.