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Forum: Do-It-Yourself 05-01-2020, 11:17 AM  
How to discharge the photo-flash capacitor of a DSLR (here K-30/K-50/K-500)
Posted By blues_hawk
Replies: 8
Views: 1,999
I see some back and forth on potential threats of potential so I thought I'd add my experience to the fray. I'm an industrial electronics technician with several decades of component level repair experience. My opinion is that any high voltage capable cap has the ability to deliver a nasty and painful shock, and in extreme cases(800vdc bus on Ac inverter type drives) can actually be physically destructive. An example of the last was made evident when a tech reached into a cabinet he thought was off and got too close to a capacitor bank. Since it hadn't been discharged he got hit by a pretty hot charge, which left burn holes from his hand to his elbow. He was lucky and walked away. --but this is the extreme. A small cap discharge is like getting zapped by static, and is almost always localized to the body part that becomes the conductor. It is very unlikely to cause heart issues. High voltage caps, even small ones can and do "space charge". It's a very old and very outlawed shop practical joke to hand someone a hot cap.
So, having been zapped too many times to count by space charged snubber caps (.1uf 600v) holding a few hundred volts, unless you could die from a sudden surprize, like...oh..finding out the truth about government, or having a cat land on your head, you generally don't have much to fear from a flash cap.
BUT! The camera could be seriously damaged by such an accident. I think this is good enough reason to purposefully discharge the cap.
Forum: Do-It-Yourself 05-01-2020, 11:01 AM  
K-5 Full spectrum conversion (IR filter removal)
Posted By blues_hawk
Replies: 20
Views: 7,168
I just thought I'd share this translation link on this important thread. It does a pretty Medex's tutorial into English.
Google Translate


Just about to ruin my K5. I bought mine because it is now one of a few Pentax cameras working well with libgphoto and have been using it remotely on my telescope mount for about a year and I have high hopes of narrowband greatness.
Forum: Monthly Photo Contests 03-17-2020, 07:49 AM  
Poll: Expired Contest Poll VOTE NOW - Photo Contest #162 Poll (Landscape in Monochrome - February 2020)
Posted By blues_hawk
Replies: 46
Views: 4,862
There is a test I do when I consider an image, including in film and even anime, and that is to ask myself "Would I frame this and hang it on the wall?"

I'm not going to say which one I voted for, because it would take away from the others.
Forum: Monthly Photo Contests 03-10-2020, 02:26 PM  
Orion + Carousel
Posted By blues_hawk
Replies: 22
Views: 795
I would like to nominate this photo
Forum: Monthly Photo Contests 03-10-2020, 02:23 PM  
Country Road
Posted By blues_hawk
Replies: 28
Views: 468
I would like to nominate this photo
Forum: Monthly Photo Contests 03-10-2020, 02:18 PM  
Big Bend
Posted By blues_hawk
Replies: 41
Views: 388
I would like to nominate this photo
Forum: Pentax Forums Giveaways 01-12-2020, 04:54 PM  
So, what did we learn from this....
Posted By blues_hawk
Replies: 33
Views: 5,951
I learned it can be difficult to find out who won things. I also learned that it can be pretty difficult to come up with 100 posts in a month without s***-posting. My album has a ton of stuff in it now.

Anybody got a link to a winners thread article or something? I can't find anything on December's drawing as the drawing thread just kind of went quiet.

[edit: just found it 1 minute later.] congrats to the winners. I kind of liked that bit they did last year where you had to be an active member before the stuff started, but I guess bringing in fresh blood helps too.
Forum: Post Your Photos! 01-04-2020, 09:35 AM  
Macro A Snowball in summer
Posted By blues_hawk
Replies: 8
Views: 280
Thanks everybody! The dark background comes from it being on a steep bank and very leafy. It's dark in there. The colors vary on those bushes depending on how you feed them. It's pretty neat to feed them old coffee grounds and get different flower colors like this.
Forum: Post Your Photos! 01-01-2020, 09:23 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Yeah that sucks.

[redated a long rant to keep PF a happy haven]
Forum: Homepage & Official Pentax News 01-01-2020, 12:11 AM  
Happy New Year 2020!
Posted By blues_hawk
Replies: 8
Views: 429
Happy new year to you too!
Forum: Post Your Photos! 12-29-2019, 10:26 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
I think I'm going to like the lens though.. here's the other way. North star near the tree on the lower left.

Forum: Post Your Photos! 12-29-2019, 10:13 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
That sucks. Maybe somebody will get up a posse and attack it before it gets out of hand. I've got tree troubles too. The tree company is supposed to come get the adult planted pines and profit share with me, but they're dragging their feet a bit.
I just got a new 14mm rokinon to play with and you can see some of my tree problem in this shot. The sky hasn't been very good this week.
.
.
Forum: Post Your Photos! 12-28-2019, 07:52 AM  
Landscape Mabry Mill in fall
Posted By blues_hawk
Replies: 9
Views: 288
Nice!

" I may have caused one of them to faint when I stuffed a 50mm f1.4 in my pocket." -- it did have covers on! :P
Forum: Post Your Photos! 12-24-2019, 01:35 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Woot, on the group. Some good folks in there. [heq5] --I did that with my 6inch sct that started the ball down this road. That's not so much a big spotting scope as it is a small stage spot. 5 years later....

Money -- I'm holding off on the big camera partly because single income and I'm doing short time right now. :P I've gotten ahead by hard work and DIY everything. It's amazing how much folks pay for services, though as I get older the ground gets colder and the roof higher and the jungle a bit stronger...

I'm a ZWO fan for bang for the buck cameras. I've seen some very good work from the QHY
PI is undoubtedly good but there are some free alternatives. I saw on your Flickr you're already using some of them. I use linux for most things and Siril for stacking and calibration, Gimp and Raw therapee for finish. I've also developed a remote setup partly with DIY stuff and opensource. Indilib.org is a great resource for that. I use a 35ah garden battery in an old hanging file folder box with a battery charger, a fused lighter jack for the mount. It also houses 5v buck regulator supplies for the raspberry pi and usb hub. I also have bricks buried in the front and back yard with holes in them for fast polar alignment and power cords and network cables coiled up under the house eaves when not in use.
Forum: Post Your Photos! 12-24-2019, 07:48 AM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
LOL! Yes.. destruction still might happen. Lesson learned...change to close up glasses when choosing photos to share.
Forum: Post Your Photos! 12-22-2019, 05:31 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Thanks!


Me too. It's mostly color balance that makes a big difference.





I got to H-alpha the cheesy way. I modified the camera by removing the filter completely(full spectrum), then used external 2" inch IR/UV filter that was well known to pass a high percentage at 656nm. The filter was inexpensive and I am able to make changes without doing more tear downs. A clip in would be neat because I could use my 62mm and 72mm lenses without vignetting the aperture with a bunch of step down rings but clip-ins get pricey.



If you go mono, be ready to deal with 4 times the number of frames per shot, and processing nightmares. In the short nights of summer that can make things very frustrating. You also need a set of filters, and a filter wheel. and a huge amount of drive space..and patience. It all adds up horribly. I cut corners whenever I can so I made my own diy motorized filter wheel from the cheapest one I could find.

Yep, on objects that have plenty of light Ir can really cut through the junk, but it can be finicky as I'm sure you already know.

If you have a camera that is passing some Ha anyway, but cuts sharply at longer wavelengths you can use an IR pass filter that includes a tiny bit of dark red spectrum effectively as a broad band filter. It's not going to be the single lum monster that a really expensive 7nm wide Ha is. I've seen the big guys(planet chasers are sensitive about telescope size) use an Ir filter to get good planetary shots in rough skies and even in daylight.

As for budgets, my wife walked in recently and said I should get a big astrocam. Seems there was a coat in blue like the one in red she has -- but I'm trained not to see such things.

I'm currently wrestling with finding a K1 I can nab on the "cheap" or spending the same too much cash on a cooled aps-c like the asi1600-pro. Since I have a couple good Pentax cameras, and way too much junk for them, the astrocam is currently winning. For me, the ROI or "region of interest" ability is enticing. But the lure of a larger mirror may win out.

^^that much rambling means I should probably plug my astro group. We're eager to please and you can get just about any question answered there in a few minutes. It may not be the right answer, but that usually just means you get to watch really smart people argue for a while. It's also let me rub elbows with some big names in astronomy, always a thrill. :P Astro group

And HEY! we need more Pentaxians in that group. I feel like that little terrier barking around the big dogs when the canikoners start arguing which is the best. Then I recently made it abundantly clear. :cool:
Forum: Post Your Photos! 12-21-2019, 04:40 PM  
Architecture Downtown, looking up
Posted By blues_hawk
Replies: 16
Views: 410
LOL! --yes we do. I carry an old Canon G1x as my commute/backup camera most days.
Forum: Post Your Photos! 12-21-2019, 12:21 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Cotton candy trees. Very nice, with a kit lens too(I still love mine). Your extra effort getting the distance set up shows.

I realized the adjustment was likely going to be a problem and just set it square to the frame. I mostly use it with a PK adapter and the Ir filter makes af in the eos-m have seizures anyway. I did buy a real M lens but it's not the greatest. It did fit in a packet though, when it actually connected. The M series(and canon firmware in general) makes me twitch a bit. I haven't really done much with IR filters as I originally did it for astrophotography. I quickly learned that I still needed a UV/Ir filter, but bought a 48mm one that passes H-alpha. It did make a difference but I don't have much to show for it as yet. It's a 3rd string experiment and there often isn't time or energy when I get that rare clear moonless night. I did get some time lapse with it after I got the filter.
















You Tube




I think it looks pretty cool in HD, which apparently is more than the internet is capable of at the moment.
Forum: Post Your Photos! 12-19-2019, 09:20 PM  
Architecture Downtown, looking up
Posted By blues_hawk
Replies: 16
Views: 410
The Reflection kind of makes it look see through. Old Qubert would be excited by that building.
Forum: Post Your Photos! 12-19-2019, 08:42 PM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Thanks!, that one is also posted somewhere else but I decided to put it in my gallery so I could cross post it easier. I'm hoping to actually get decent at this at some point but it's seriously a sideline thing.

The hardest part is the 2 hours of meticulous disassembly and then carefully cutting out of rubber, (and usually destroying) the built in ir/uv filter in the mirrorless eos-m without destroying any of the ribbons or micro sized connectors, and then carefully reassembling the whole mess and having it work. I used a slowed down video example of the operation and recommend at least a point by point I looked it up and the K5 is even more freaky to convert. I'm considering getting a second k5 for a backup before trying this operation on it.

Word of warning: Warning, there is soldering involved in the pentax takedown. I have 30+ years experience in component level electronics repair, so I'm not going to be pushing anyone to try this at home. If anyone decides to try it on their own be sure to find step by step instructions and understand them before you start, and use containers lined up to split parts into as many logical steps as possible....and clean...now clean again. now clean the air, now throw the cat out. Lifepixel is a much easier option and sells used gear too. I wish they had a k5 already done as they make very reasonably prices astrocams now that we can reliably tether them. I get enough HA (ionized hydrogen emits at near IR wavelengths) in the K5 without conversion that it may not even be worth the risk.
Forum: Pentax Forums Giveaways 12-19-2019, 08:40 PM  
PentaxForums 100 Year Giveaway - December/January - Grand Prize Raffle Entry Thread
Posted By blues_hawk
Replies: 167
Views: 6,386
Made it this time! I would love to have the new flagship so I could help sort out tethering for that one too. :D
Forum: Post Your Photos! 12-19-2019, 08:36 PM  
Landscape Icy mountains.
Posted By blues_hawk
Replies: 2
Views: 219
I took this one last winter.

Forum: Post Your Photos! 12-19-2019, 09:32 AM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Cotton candy factory exploded.:D
Forum: Post Your Photos! 12-19-2019, 09:31 AM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
Here's one that IR worked better on. One thing I noticed when I started trying to do this, it basically the same techniques as long exposure night shooting, especially if you use a very long wavelength IR filter. I was taking 6 second shots even with the gain pushed.

Following my other experiments with super long exposure low gain shooting, I suspect this can get much better with a tripod and iso100. I'll try that sometime soon.

Forum: Post Your Photos! 12-19-2019, 09:02 AM  
Landscape infrapink
Posted By blues_hawk
Replies: 29
Views: 791
In my defense, this was a day after I converted the thing and just really wanted to play with it. I ended up taking it to work and then this was on the way home. That's usually a pretty decent shot unless I'm blocking the one "traffic" that comes along...and that's a school bus.

[well maybe I "think" it's a decent shot, since I don't have one to show. lol]
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