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Forum: Pentax K-5 & K-5 II 02-18-2012, 10:08 PM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
E/W alignment v. N/S. It will not calibrate along the N/S axis and, the cal process is often 'mysterious' (see above comments from the OP) probably relating to this issue. I also noted earlier that the tri-axial calibration method in the standard setup indicates completion after only 2 axial rotations. When I did figure out the E/W issue I still was left with trailing stars (200mm lens @ 30 sec exposure, well below the maximum allotted for the focal length).



^This

Regarding the trad method of astrophotgraphy, I'm well aware of what's in store regarding mount costs and expectations of results. The point I'm making is, that within the typical framework I can learn to a better degree the art and craft and have more control over the inputs even at the beginning level. The O-GPS1 seems to have too great a 'mystery' regarding it's setup and use at this point and I sense too much lies within 'the box' for me to get a better grasp or at least to trust implicitly. The GEM route is well documented and there is plenty of literature to hold my hand as I learn as well as being completely extensible to all comers.

In the end I was probably asking too much of the device and its concept, and after taking the plunge figured out that if I want to continue with astrophotography, I'll need to start with the basics and go from there.
Forum: Pentax K-5 & K-5 II 02-18-2012, 05:51 PM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Well I've sent mine back. I just wasn't happy with how the unit functioned with regards to the calibration method(s) also the results in usage were disappointing for me. I will probably get an GEM mounted scope and work on astrographs from that standpoint.

I will say that the concept of this unit is an excellent idea and I hope that Pentax will sort out the calibration issue as well as provide a more detailed usage manual.
Forum: Pentax K-5 & K-5 II 02-14-2012, 11:26 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Brillilant! If you have a disused flash, remove the hotshoe and epoxy it to the scope!
Forum: Pentax K-5 & K-5 II 02-14-2012, 09:50 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
I've been pretty lucky, the targets I've attempted to shoot are easy enough to bring into view (even with a 500mm).

Actually any inexpensive scope would do the trick I suppose, check swap meets/yard sales even.

As for simple mounts, I thought I saw a generic mount but all I can find are ones that are for through the eyepiece shots or scope specific mounts for piggybacking.

That said one could adapt a tube ring with a 1/4-20 screw but simpler and cheaper than that, I'd use some plumber's tape (even better a hose clamp) with a 1/4-20 bolt through the strap. Attach the camera first to the strap, then wrap the plumber's tape around the scope and bolt the ends to snug it up on the scope tube.
Forum: Pentax K-5 & K-5 II 02-14-2012, 08:17 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Or just piggyback it on any decent reflector...
Forum: Pentax K-5 & K-5 II 02-13-2012, 07:17 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Hmmm my shot above was shot due south at a pretty high declination and I was under the impression that shooting above a certain degree in declination one was out of luck, though what that exact figure was or would/will be was largely dependent on global location. When I have some clear skies I'll try this to see how it works for me at my latitude.
Forum: Pentax K-5 & K-5 II 02-12-2012, 03:07 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Here's the last attempt at usage:



Stack of 7 images, 200mm kit zoom - 30 seconds @ 3200iso.

I'm probably out of my league attempting to capture this object in the first place, but what the heck. I need to keep shooting and improve my technique. I'm going to give it another go after I calibrate the unit properly and the sky is yielding to my efforts. I do want to add that the program I used to stack the images is not very forgiving in terms of user interface, so I think the hint of trails present may be due in part to the rotational aspects of the app than the O-GPS1 (though some is present in the originals, I 'm suspecting my lack of usage with the app helped create more... I think).
Forum: Lens Clubs 02-12-2012, 02:43 AM  
The Mirror Lens Club!
Posted By d00d
Replies: 1,239
Views: 467,314
Some Celestron 500mm images (no birds...):

Donuts? Who likes donuts?



These guys of course!



The following need no introduction...




(7 images stacked)

I guess it's pretty typical with regards to contrast. The first 2 shots were handheld, the others I shot on a tripod and used the remote with mirror lockup. Focus is difficult at best. I tried to capture a bird when I was snapping the rescue crew and well, I now have a healthy respect for those of you that photograph birds! I think I'll continue to use it for astrographs of the sun and moon and maybe some deep space objects if I can improve my technique. For $25 total outlay, what did I expect?
Forum: Pentax DSLR Discussion 02-12-2012, 01:55 AM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
Vincent, very instructive and I'll need some time to digest for sure. A quick G-search on LED spectrum yields mostly grow-light info for "herb" cultivation...

I attempted to replicate your results with the challenge image and forgot that you had performed the balancing act on the jpeg whereas I used the RAW image and found myself a little further from my first post work.

So as mentioned I'm posting some images of a band shot at a bar using LED stage lighting, and in addition the light there was for all intents crap. No spread, little diffusion just wrong for the purpose. Yet I was able to render something from my efforts. Initially I resorted to making the final output monotone or some variant thereof, but after playing with some recent shots and creating a workable preset in LR, I applied that for experiment. The results as follows:

Again (like Mark Sabatella), my first response to this lighting was to make the image either straight b/w, sepia or cyanotype. All are 25600iso, f/2.8 (and I forget the shutter speed):



Here's Amanda in modified color (her hair is pretty much that color):



Here's what can be done with nothing (or so it seemed):



(I didn't attempt to rework this one in color as I liked the final outcome in sepia)

Again, my first instinct was to make a monochromatic image:



But with a new light (Ha!), I can see in color now:




Though this one is interesting with the greenside light, I found the color background distracting so I went for a duotone effect (name drop here, Jim Croce's son AJ)



The full set of images as I first processed them is here, and actually I like them the way they are for several reasons: 1) I'm partial to black and white 2) Funky soul and jazz is best viewed under dim lights and the graphic reduction that b/w imparts and 3) sometimes it just comes together best in this manner (maybe I'm old and have too many William Claxton/Jim Marshall images swirling around my head when I shoot and process the results).

That said, I'm glad to find some effort on mitigation of what I find as deleterious effects of LED lighting for photography, because I'd like to have options in the editing stage and now I've found that I can. Cheers to Vincent!
Forum: Pentax DSLR Discussion 02-10-2012, 11:59 AM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
I think I was close to that area but I believe selected a whiter shade (of pale...). I'm going to make a test and try that area and see how it turns out, mostly just out of curiosity to see how color space and management between OSs may differ. Can you give me the co-ordinates from your selection point (if they have saved with the image)?

I wonder if in theater they adhere to some form of standards to compensate for this variability, I imagine so (R= 4/B=2/G=5/Y=0 that sort of thing). I had considered the spectral nature of the light from them but hadn't seen any charts or read up on it in the least. I know that as a light source LEDs have a peculiar quality about them and I can see this in auto tail lights when I'm driving. My retinas respond differently to them and they have an odd persistence that other forms of lighting does not. i don't know how to explain it further and I've not really mentioned this 'quality' to anyone (thinking they might think me nutty...).






QuoteQuote:

In clubs of any size - most will probably have mixed lighting and use different colors on different parts of the stage -
so I think to try to balance things so that the faces are reasonable and giving guitar finishes the equivalent of studio lighting - is probably nigh on impossible with a single correction point -



True, but that's why I included the last 2 images. I wanted to show the range of lighting I had experienced thus far and that in those 2 examples I was able to get a very good balance. It seems to be the extreme (naturally) that causes the most issues. Kinda like politics or religion lol

Same here and I thought about that but then my workflow would need to make a side trip down Photoshop way, which if I felt the image needed that degree of control and adjustment I'd certainly go there. I am impressed as well and I'm glad I found this thread and that you have put a good deal of effort into the issue to find solutions as well as create discussion of the matter (which is extremely helpful I feel). Thank you for those efforts!

I have some other images from past shoots I'm going to reevaluate and post.
Forum: Pentax DSLR Discussion 02-09-2012, 11:51 PM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
So here's some of my post work with the challenge files of Vincent's along with some before and after screenshots then with some of my own for further discussion.

This is the DNG file processed in LR3:


Same file processed in PDCU 4:



Now the Jpeg file in LR:



And same in PDCU4:



Some things to note (besides the white shirt...): The green spotlights, keeping the same or similar color in LR was difficult, PDCU had little issue. The blue jeans. Now balancing the jeans with the skin tones and the green spots was interesting. The Fender bass. This is the biggest problem for me regarding these lights or at least the use of the magenta/purple ones. Besides making a magenta glow on relevant points of interest (faces and such) that produces a false out of focus look, balancing the color across the board seems nigh impossible. Below are some examples of mine from the other night to illustrate this point.

Note the guitar finishes. The Les Paul is a gold top and the Rickenbacker is fireglo:



The Les Paul closer to it's actual finish, note the Rick 4001 to the left and the corner of the Rick 6 string. Both should be fireglo (a reddish sunburst):



And a closer shot of the Rick 6 string in all it's fireglo glory:



I may be asking too much of everything concerned to get something approximating normalcy, and I have some shots below that prove everything (camera, PP apps, my color vision) is certainly very capable of managing the task at hand.



For the above shot I used the microphone (Shure SM56) as my point of reference for neutral. It was pretty darned close!

It could very well be that the lighting was more subdued and hence easier to manage color balancing, but the lighting rigs looked very similar and I suspect they were the same though maybe the second club's setup included more white and such. I'd only been there the one time so I had little to go on in that regard.

Most of the shots are at 25000ISO with a 2.8 Tamron zoom, the last one being 12600ISO. I created a preset in LR as a starting place for this type of lighting. Mostly it involves the white balance and the camera calibration and then I tweak the hue/saturation/luminance of various colors as they might influence the scene.

I want to add this point: I do not like the color of these particular LED lights, matter of fact I don't like overly strong variants of RGB in hot lights as well. I used to have problems shooting film with overly red spots at one club I frequented (since gone LED...).

So to sum up my feelings about all of this; my efforts are in abating the magenta/purple cast as much as possible and restoring some degree of average to the color balance as a whole and that being said, I'm not so sure it's possible. I may have to just find some happy medium that involves the original color spectrum, as you have Vincent with the shots of the girl singer in the vinyl dress. I will of course buck this to the end though... ;-!
Forum: Pentax DSLR Discussion 02-09-2012, 11:59 AM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
Indeed I do (4.34) and unfortunately running it on OSX is probably the most frustrating of all, I can't believe the product was released with such a poor functionality. It is unbelievably slow!

I will say that PDCU produces a better white balance than LR in quicker fashion. I sensed from your examples and from dvest as well that this might be the case, but in playing with them found it to be true. One thing I having the most difficulty with is getting certain colors even close to right. Guitars are especially hard. Being a musician, I know intimately finish hues and such, and balancing them out with skin tones and other items has proven difficult as such.
Forum: Pentax K-5 & K-5 II 02-09-2012, 07:52 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Gotcha, I had considered something along those lines (changing up the order of rotation). I'll give that a shot here in the next day or two. Thanks!
Forum: Pentax K-5 & K-5 II 02-08-2012, 03:20 PM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Exactly! I rotate the camera a full 360 on all 3 axis by hand. And why does it claim calibration for me after only 2 axial twists are given during the basic calibration sequence?

Also note the 'Notes' section, so I should leave the camera back in Kamuela instead bringing it up to the summit on Mauna Kea (WM Keck)? lol! And I wonder how much influence underground electrical wires would have?
Forum: Pentax DSLR Discussion 02-08-2012, 11:01 AM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
Vincent, I've downloaded your 'challenge' files and played with them in both LR and PDCU4 and will post the links soon. I also have some of my work to show as well along with before and after screenshots in LR. I will also discuss my observations of working with these files in both applications at that time.
Forum: Digital Processing, Software, and Printing 02-08-2012, 09:54 AM  
Pentax Utility (newest 4.34V) running painfully SLOW on my Mac
Posted By d00d
Replies: 4
Views: 1,414
No go diggy di...

Well when I eventually transition over to Windows I'll give it another shot.
Forum: Digital Processing, Software, and Printing 02-07-2012, 09:45 AM  
Pentax Utility (newest 4.34V) running painfully SLOW on my Mac
Posted By d00d
Replies: 4
Views: 1,414
I'm gonna give this thread some action as well because I installed it the other night (right click on CD>Show Contents...) and then had to update it straight away due to it crashing.

But yeah I can't even work with the program it's sooooo slow! I'll try a restart and make sure nothing else is running, but suffice it to say I'm glad I bought LR!

I will say though that PDCU does do a great job with white balance, problem is I don't have all night to balance images lol
Forum: Pentax DSLR Discussion 02-05-2012, 01:05 PM  
Modern LED Stage Lighting & photography problems
Posted By d00d
Replies: 191
Views: 80,504
Coming into this a little late but I'm glad this thread exists as unlike Mark, all I run into anymore are these damn lights and have had a hell of a time getting usable shots to the point I didn't think it possible to get a reasonable white balance out of them in post (in camera was a waste of my time to try and sort) and would just desaturate to b/w or some variant thereof due to the overly magenta/purple wash on everything.

I'm going to read through your work see if I can adapt the techniques to my workflow (LR3) and post some results.

Thanks again for your efforts in finding a workable solution to this lighting.
Forum: Pentax K-5 & K-5 II 02-04-2012, 10:09 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
I'm going to say no. The calibration mystery still exists here in N. America at the 33rd parallel. My rig won't even calibrate when positioned N/S, only when I turn 90° will it calibrate in any mode. The compass and GPS modes are not why I bought this item and being frustrated in the operation of the device makes my enjoyment less than 'stellar'. I may just get a decent scope w/GEM and try the traditional approaches.

The other issue is with stacking software. I've been using Keith's Image Stacking and it's got a pretty large learning curve and doesn't seem to tolerate inexperience with the UI. I cannot get a grip on running GRIP on a Mac, so I haven't tried that yet.

Stone G.- The 'Camera Settings' link is brilliant and a must read for all who endeavor into astrophotography

Overall I think my experience is muddled by a middling lens (50-200 4-5.6 kit zoom) and not enough experimentation/experience with astrophotography, but I think the device has promise in the hands of a more experienced person.
Forum: Pentax K-5 & K-5 II 01-26-2012, 07:22 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
And here's some informational pages for further reading on the subject:

How Image Stacking Works

grelf.net - Camera following the stars
Forum: Lens Clubs 01-22-2012, 04:08 PM  
The Mirror Lens Club!
Posted By d00d
Replies: 1,239
Views: 467,314
I'm looking forward to get a chance to shoot with it! lol I got the proper T-mount adapter, now I just need a some free time and an interesting subject... Oh wait I hear birds!
Forum: Pentax K-5 & K-5 II 01-15-2012, 12:09 AM  
K5 & O-GPS1 for astrophotography: Pix and experiences from Namibia
Posted By d00d
Replies: 119
Views: 88,031
Wow impressive shots!

I just got mine today and am frustrated by the lack of understanding on my part and the dismal failure of the manual to inform me better. I'm not even sure if this is functioning properly, the battery indication light has yet to illuminate and the Sat light blinks at me regardless. The calibration method only gives me an OK after I've done 2 of the 3 axial rotations! I had the GPS indicator showing on the top LCD at one point but now it's gone.

I think I just need to return it and get another... Bah!

Any thoughts/suggestions/postage greatly appreciated.
-----------------------------------

OK never mind... I guess the unit can't receive anything inside the house. I took it outside and after a short span it locked on.
Forum: Lens Clubs 01-09-2012, 12:33 AM  
Zeiss M42 club?
Posted By d00d
Replies: 142
Views: 87,352
Kinda quite in this corner of the Pentax forums...

I bought a CZJ 58mm Biotar a few months ago and have played with it some and thought I'd join the club (if the dues are low... or is there a handshake I need to learn along with some passages from an arcane book?). Picked up a proper Pentax adapter and a neat Olympus hood for a 60/1.5, works great at keeping my fingers off the front element. Here's some samples:

----------------
Hmmmm What happened to my links?????!!!
----------------
Dag nab company firewall... Nvrmnd


Forum: Lens Clubs 01-09-2012, 12:03 AM  
The Mirror Lens Club!
Posted By d00d
Replies: 1,239
Views: 467,314
Just acquired a Celestron 500 f/8 mirror for $20 from the swap meet and figured I'd join in the fray here as long as the dues are low.

I'll need a proper T-mount adapter to check it out on my K-5 and post the results. I see some issues with the secondary mirror around the edge and the main mirror looks like some dust has collected on it, but it seemed to focus ok on the Canon body I was able to mount it to before buying. Came with a Tiffen Sky 1-A and the hood, I forgot about the crazy donut bokeh with these things!
Forum: Welcomes and Introductions 10-10-2011, 12:55 PM  
istDs to K7 or K5
Posted By d00d
Replies: 5
Views: 972
My first dSLR was from the *ist series, I took a detour at the Leica offramp and then took a left at the K5 expressway. The video feature was not the selling point to me, it's a nice feature to have although it is not as mature as the competition. I'm mostly interested in high iso capabilities and the in body SR.
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