Alley in Pisa, Italy

by Lars Kotthoff

submit your photo


Hall of Fame
View past winners from this year

Please participate in Meta
and help us grow.

1,708 reputation
49
bio website blog.migol.com
location Menlo Park, CA, USA
age 46
visits member for 3 years, 1 month
seen Jul 22 at 20:30

About Me Amateur photographer looking to expand my knowledge. I started shooting with film and played about with manual SLR for many years. Switched to P&S digital for a while then graduated to DSLR. Over the years I've tried my hand at abstract macros and a few other memes. Recently joined a Meetup group of photogs to learn studio lighting.

Pentax Equipment

  • Pentax K10D x 2
  • Full-spectrum modified Pentax K10D
  • smc P-DA 14mm F2.8
  • smc P-A 28mm F2.8
  • smc P-DA 35mm F2.8
  • smc P-FA 50mm F1.4
  • smc P-D FA 100mm F2.8
  • smc P-A 135mm F2.8
  • smc P-K 200mm F2.5
  • smc P-A* 300mm F4.0 smc P-DA* 16-50mm F2.8 ED/AL (IF) SDM
  • smc P-DA* 50-135mm F2.8 ED (IF) SDM
  • AF-540 FGZ x3
  • Pentax 67 bodies and lenses
  • ... and a couple of telescopes!

Jun
21
awarded  Yearling
Aug
19
comment Continuous Bursts of Many Short Exposures vs. A Few Long Exposures for Astrophotography?
In practice, I've found that without some active cooling, the sensor will not cool down between shots. Additionally, if you are doing noise processing after the session (which is ideal), you want the camera to reach a stable temperature quickly. Only once it's stable will the noise profile be consistent. Also, using deeper subexposures will help bring out far fainter objects - useful for guided star pictures, not so useful for star trails.
Aug
14
answered Can you photograph the milky way with a full moon out?
Aug
2
comment What causes faint circles in astrophotography images?
These do look like an artifact that is introduced at the filter level. You can test the source by: 1. Rotating the camera position 2. Rotating the filter if it's an external one You can eliminate most of these artifacts by taking flats and using them in your processing. A flat field will show the profile of light fall off and will provide a reverse curve for calibration.
Jul
30
awarded  Citizen Patrol
Jul
29
answered How do I convert a single FITS image into Red, Green and Blue images?
Jun
21
awarded  Yearling
Jun
14
answered What camera equipment do I need for deep space photography?
May
7
answered Does a filter exist to color-correct color negatives when copying them with a DSLR?
Apr
10
answered Is Poisson Noise (“Shot Noise”) a significant source of noise for typical photography?
Feb
26
comment Is it better to shoot with a higher ISO, or use lower ISO and raise the exposure in post-processing?
Absolutely it's a specialized case. The important thing to note is that Canon is doing noise reduction at the raw, creating part of the different performance of the ISO levels. Thus, the example given may not be identical and it may not be as strictly controlled as originally thought. Still, this is a corner case.
Feb
25
awarded  Critic
Feb
25
comment Is it better to shoot with a higher ISO, or use lower ISO and raise the exposure in post-processing?
In the astrophotography world, people are using Canon DSLRs extensively and have split the hairs on the ISO question. Craig Stark has run the numbers on some Canon product and published a detailed analysis of linearity of data from these cameras: Profiling the Long-Exposure Performance of a Canon DSLR (July 2, 2012, Cloudy Nights) stark-labs.com/craig/resources/Articles-&-Reviews/… In a nutshell, he says that Canon is modifying the dark signal before it hits the raw file and that settings above ISO 400 are of limited value.
Feb
15
answered What special equipment is needed to photograph the sun?
Feb
13
answered How can I import Pentax lens information into Lightroom?
Feb
6
comment How to shoot stars much bigger without trails?
Might want to look at what Hutech offers as a constellation filter. Looks like this might have been used on this shot. sciencecenter.net/hutech/kenko/softfilter/index.htm Photographer Alan Dyer talks about his method of using the filter on his blog: amazingsky.net/2011/02/21/fuzzy-constellations
Feb
5
answered How to shoot stars much bigger without trails?
Oct
15
comment How would I setup a portrait of a boxer like these?
A lot of studio lights have a continuous light for modeling - allowing you to see how the light falls on the scene. These modeling lights also act as a visual reminder that the head has recharged. Any ambient light from other sources is usually drowned out by the flash, so you and the model are not in the dark.
Oct
15
answered Advices for a good studio lighting photography book?
Oct
11
comment What's the best way to shoot aerial dancers in low light conditions?
That's exactly what I was trying to imply with the dynamic comment. It takes a practiced eye to see what kind of movement looks best, too.