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Forum: Pentax DSLR Discussion 09-28-2011, 05:35 PM  
K20D and Long Exposures
Posted By LeoTaylor
Replies: 10
Views: 3,862
As someone who took many hundreds of 2 minute astrophotos with a K110D rest assured I did not hold the button all that time. :p

At first I used the Pentax cable release, a bit pricey at $44. Simply a two step switch with a locking position. Then I switched to various timers that plugged into the Pentax. These allowed multiple images with a delay between them.

Be glad our older models have a jack for external shutter switch, some newer Pentaxs do not.
Forum: Pentax DSLR Discussion 09-28-2011, 05:17 PM  
Is it normal for K-x not to be able to AF on a white wall ?
Posted By LeoTaylor
Replies: 8
Views: 1,676
Most things my K100D can't focus on (White Wall, Empty Blue Sky, reflective plastic) are things I have no desire to photograph.
Forum: Pentax DSLR Discussion 09-21-2011, 07:23 PM  
Computer Remote Control for Pentax?
Posted By LeoTaylor
Replies: 8
Views: 9,991
Sure, I'd love Pentax to support Remote Control better. But I gave up waiting for them long ago. I have four versions of K1x0D cameras. They are not supported by Pentax Remote Assistant whereas the *istD (older) and K10D (newer) are supported. I assumed it was an oversight and Pentax would correct the mistake!

What I used for astronomy was DSLR-Shutter from Stark Labs.

DSLR Shutter

I made a two simple interfaces from Serial to Pentax Shutter jack. One is relay based and requires power, the other is Opto-Isolater based and self contained. You can set exposure, interval, and count. Nothing fancy but all the functions I needed.

Works fine with my old HP observatory desktop, old HP laptop, and new HP laptop via USB to Serial converter. Software is free though a donation would be nice.

Leo Taylor
Forum: Pentax DSLR Discussion 04-11-2011, 05:24 AM  
Why you should shot RAW!!!
Posted By LeoTaylor
Replies: 30
Views: 6,095
I didn't see anyone mention the main reason I use RAW unless there is a pressing reason not to (usually speed). The 12 BIT resolution allows me to salvage dark areas of the images that would be black in a JPEG. I expose for the brightest spots not saturating thus the darkest areas may appear black. With RAW there are still several levels of gray scale in the "black" and with PSP 12 I can expand the bottom end without saturating the top. I improved many a photo that way. With 8 NIT JPEG Black in the preview is indeed black.
Forum: Pentax DSLR Discussion 03-28-2011, 07:47 PM  
catch in focus is such a wonderful thing
Posted By LeoTaylor
Replies: 55
Views: 17,266
You don't need a camera with a built in feature to enjoy Trap Focus. I posted instructions on this forum a couple of years ago on how to do Trap Focus with a K100D. I set up my camera with a Pentax Macro lens (contacts covered with tape) and aimed just to one side of my squirrel feeder. I locked the shutter and went inside for 90 minutes. When I came out the camera had taken 900 frames! I liked this one:
Forum: Pentax DSLR Discussion 03-28-2011, 07:36 PM  
Eneloop clones at Lidl
Posted By LeoTaylor
Replies: 12
Views: 4,751
I use Sanyo Eneloops and for a K1x0D Eneloops make a huge difference. I soon discovered my K100D was far less tolerant of voltage droop than other cameras (including the istD). NIMH batteries failed quickly in the K100D and I could put them in other cameras and they would continue for hundreds more shots.

I used to replace NIMH sets a couple of times per year because they would indicate low battery soon after I started shooting. I just checked and the Eneloops I'm using were bought May 2008 and January 2009.
Forum: Pentax DSLR Discussion 03-28-2011, 07:22 PM  
Why do some move from brands so quickly ?
Posted By LeoTaylor
Replies: 47
Views: 7,319
Since my wife gave me her K1000 (and bought another) in 1997 I have not bought any non-astro camera except Pentax. She had built up a collection of lenses and we ended up with a lot of low cost K mount lenses (mostly Pentax).

The only time I THOUGHT about buying a Canon was because I do a lot of Astrophotography and Canons are much better supported by astro software.
Forum: Pentax DSLR Discussion 02-21-2011, 02:52 PM  
Oops, I moved the sliding thing with plus and minus behind the eyecup... What is it?
Posted By LeoTaylor
Replies: 14
Views: 2,975
That is the way I do it. Independent of lens, lighting, subject. I focus the digits on the bottom of the display, often after half pressing the shutter to get them to light up.

To mention something new to the thread....

I have four K1x0D cameras. All have the diopter slide one click left of center. This is amazing consistency between cameras and helpful to know. If I knock the slide askew I no longer need to focus, I just set the lever back to 1 notch left of center.

If you find the setting that matches your eyesight then you can make note of it for future resetting.

BTW: My first evening with a DSLR (K100D) I was using an old manual Sigma 70-210 from my K1000 days. I did not realize the slider was bumped toward one end and not knowledgeable to realize it. Of course every photo was blurred!
Forum: Pentax DSLR Discussion 01-25-2011, 11:26 AM  
K-x is king for long exposures and astrophotography!
Posted By LeoTaylor
Replies: 172
Views: 101,558
Good suggestion Raybo. I use the Hutech IDAS 48 mm Light Pollution Filter almost all the time. It fits Telescope 2 inch eyepiece holders directly, but with adaptors will fit most lenses. For example I just mounted my IDAS to a DA Pentax 50-200 using 52-49 and 49-48 step down filter adaptors. The adaptors are cheap enough for me to acquire a collection so I can put filters on most all my lenses. If you go way down like my 19 mm Vivitar which is threaded for 62 mm down to a 48 mm IDAS you may get some vignetting, but I've done it.

Hints: The 48 mm adaptors are not common in camera stores, I have a Kalt 49-48 and use the 49 end to go to all other sizes. Be aware some companies are not consistent as to what direction Step Down is or which number appears first on their web sites. I've bought a couple that, "went the wrong way." :hmm:

If you live in a city with visual MAG 3-4 sky like me, you gotta use an LPR filter.

Here is a dark site image with a filterless K110D and a Sigma Zoom at 210mm, I don't think I had the IDAS filter at the time. 30 seconds * 25 images. NGC 2024 & B 33 & NGC 1997 & M 42 & M 43 in Orion.
Forum: Pentax DSLR Discussion 01-05-2011, 04:04 PM  
Shutter actuations on Pentax DSLR
Posted By LeoTaylor
Replies: 27
Views: 8,418
That was ricoh.pentax with his K200D.

100,000 or 150,000 are often claimed as rated lifetime by the manufactures and it takes a long time to reach that point. Often the shutter isn't the first thing to fail, but the fact that several of us are beyond 20,000 on cameras as old as K100Ds indicates Pentax makes a good product.
Forum: Pentax DSLR Discussion 01-05-2011, 03:44 PM  
K-x is king for long exposures and astrophotography!
Posted By LeoTaylor
Replies: 172
Views: 101,558
Hi phatbob02

I'll go down your list line by line.

> I just posted the release bracket to help the NewBees.

As I started out my message, I think you did a fine job. But since I take typically several dozen 3 minute frames per night I don't want to hold my finger on a mechanical shutter release. Besides, it's cold out there!


> I purchases the Kx for the sensor, not requiring mods, and because of the price of just over $500.

Fine again. I purchased my K110D new for $349 for astrophotography only. I only used it four days before I opened it up and removed the IR filter. I broke it in the process, had Pentax fix it for $210, still had an astro DSLR for less than the cost of a professionally modified Canon. I used it for several years. It currently has 10,600+ shutter clicks, almost all astro. I don't want you to think I don't like DSLR astrophotography.

> I can live with not turning off NR over 30".

OK, but many can't as you can tell from the number of complaints that has been brought up since the K20D came out. At first many assumed it was an oversight and Pentax would fix that in a firmware upgrade. I think all Pentax cameras with CMOS sensors don't allow NR to be totally disabled like the K1x0Ds.


> And, the Kx external power supply is available. Pentax K-AC84U AC Adapter Kit.

I wrote there was a kludgey method that uses the same power supply as the K100D. For less than a nickle they could have put a jack on the outside.


> There are people out there getting great results with this camera.

No doubt, the Initial Poster likes it very much.

> I'm "old School" when it comes to AP. I use to hyper my own film.

You're brave. I used a K1000 for several years with refrigerated film. My wife would not let me hyper, "too dangerous to have compressed gas in the house." She was a lab technician and has seen gas cylinders fly across rooms and through walls.

> I own a SBig St-237 and ST-8i.

You have seen the promised land.

> Not everyone has $4500 to shell out for an ST4000XCM, and I think you're comparing apples to oranges.

Absolutely, though I only paid $3750 from OPT. I had reached my limit with the K110D. I was spoiled by the DSLR one-shot-color but wanted to go back to a cooled camera since my ST-7E cut through my light pollution far better than film or DSLR. I can easily capture image MAG 19 galaxies from my MAG 3 sky. I sold the old SBIG to help pay for the new SBIG..

Nothing in my observatory cost me over $900 (the price of my used SCT) except the SBIG. I normally do photography on the cheap, but there was no way around buying an SBIG for me to move forward from the DSLR.


> For NewBee's, this is a great camera to start with.

Perhaps. As I wrote I almost bought one for the features it has over my K110D. Unfortunately it took away features as well.

> If you're thinking of getting into AP, I would recommend a good motor driven mount.

I use my LX200 Classic as a motor drive for a refractor, camera lens, and my 2080 OTA. One motor for all worlds. :) On those occasions I go remote for darker sky I use a CG-4 with RA. motor.

> Not all of us need software to turn on this and turn off that.

I'm not sure what you mean by the on and off part. I do use software (or a timer box in the field) to operate the shutter. I also use software to point the scope at a target. With the DSLR that was about it. With the SBIG all camera operation must be with software, it can't function on its own.
----------------

My point is you can do astrophotography with a Pentax DSLR, I did for several years (and over 10,600 shutter clicks). I used my K100DS for the lunar eclipse because SBIGs don't do solar system imaging well. I'm just frustrated that Pentax seems to go out of their way to thwart astrophotography. They remove jacks that cost practically nothing. It troubles me when after years of them ignoring requests for a menu option to disable NR someone tricks a camera into factory debug mode and finds such that option exists hidden inside.

I love my Pentax cameras for daytime photos. I can even use my astro modified filterless K110D as a killer IR camera. I measured 100 times faster IR response than my K100Ds
Forum: Pentax DSLR Discussion 01-03-2011, 08:50 PM  
Shutter actuations on Pentax DSLR
Posted By LeoTaylor
Replies: 27
Views: 8,418
Now there is a serious user!

My DSLRs as of October:

istD 7190 (from display, not found in EXIF)
K100D 3397
K100D 18859 (it is over 20K now)
K110D 10687
K100DS 7095 (bought used)
Forum: Pentax DSLR Discussion 01-03-2011, 08:23 PM  
K-x is king for long exposures and astrophotography!
Posted By LeoTaylor
Replies: 172
Views: 101,558
I appreciate your effort and it looks like a great job making a cable release. I once made a similar bracket of metal to go over the button of a Nikon CoolPix. I used the mechanical cable release from a K1000 SLR to press the Nikon's button.

But....

You are in a thread about long exposure astrophotos. What is missing from the Kx that my older K100Ds and filterless K110D have and everyone wants is an electrical cable release. We want a computer or handheld controller to time dozens of exposures of minutes each.

I once came within an hour or so of ordering a Kx. What stopped me is when I read on this forum that it lacked the electrical connector for a cable release, the connector for external power, and the ability to take long exposures without Noise Reduction (AKA Dark Frame). All these items are on a K100D.

These anti-astro changes on the new Pentax models are what drove me to stop using my DSLRs for astro and buy a new SBIG ST4000XCM. My DSLRs are wonderful for daytime photos.

I have recently read that some of the new Pentax cameras have been hacked and there is an option in the Debug menu to turn off NR.

There is a kludgey power adaptor that you insert in the Kx battery holder. It has a lead with a connector that goes to the same power supply that plugs directly into a K100D.

I did mount a K100D Super on a scope for the recent Lunar Eclipse. Power, Electronically timed shutter, no NR - I used all the features the Kx does not support.

Finally my K100Ds are not supported by Pentax Remote Assistant. I can't control the shutter through USB on any of my DSLRs except the istD.

I hate to sound down but starting with the K20D with not being able to disable NR for long exposure I feel Pentax does not care about us astrophotographers.
Forum: Pentax DSLR Discussion 12-13-2010, 05:59 PM  
Focusing Screens K-7 Astronomical
Posted By LeoTaylor
Replies: 7
Views: 2,458
I've been focusing astrophotos since 1997. If you mean a focusing screen internal to the camera I can't see how that would help when you are looking at the night sky. I had a K1000 with split ring focus aid, the focus screen was useless in the dark.

What I use is a Bahtinov mask from this company:

Bahtinov Mask by Focus-Mask

I have two, $24.95 for my refractor and $34.95 for my SCT. The smallest one they make >might< even work on a lens or you can make a smaller one from plans.

Unlike ALL methods I tried in the past, the Bahtinov:

1. Tells you the direction to go. No more guessing one way to see if it is right, then having to start over the other way if you guessed off wrong. Think about it, that is how we manually focus cameras during the day. Turning back and forth to find the best focus!

2. Tells you when you are already focused. Other methods require you to unfocus to discover you were already at best focus. I check focus on occasion throughout the night. With the Bahtinov mask if the cross bar is centered I'm done without touching the focusser!

If you are on a tight budget Focus-Mask lets you download their actual layout so you can make your own. But, the black plastic ones they sell are hard to beat.

Once I tried black I never went back to the old way of focusing astrophotos.
Forum: Pentax DSLR Discussion 11-07-2010, 08:40 PM  
New Pentax FF
Posted By LeoTaylor
Replies: 63
Views: 11,984
I've impressed many Canon-Nikon owners by telling them new Pentax DSLRs are compatible with every lens Pentax ever made since before Canon and Nikon existed.

If they come out with a full frame they will have to drop one of their great advertising points: backwards compatibility.
Forum: Pentax DSLR Discussion 11-07-2010, 08:30 PM  
Should I worry about my K100DSuper shutter count reaching 22,000?
Posted By LeoTaylor
Replies: 6
Views: 2,167
Most companies avoid specifying lifetime but from what I've read it is typically 100,000 to 150,000 shutter clicks. You have a long way to go.

Something else could fail long before the shutter dies.
Forum: Pentax DSLR Discussion 11-07-2010, 08:07 PM  
Astrophotography
Posted By LeoTaylor
Replies: 1,132
Views: 258,501
RipDaJacker,

Stunning photo for anyone, let alone a beginner. You captured the faint wispy wings as well as the Trapezium stars. I would have said it could not be done with such short exposures.
Forum: Pentax DSLR Discussion 11-04-2010, 07:31 PM  
Astrophotography
Posted By LeoTaylor
Replies: 1,132
Views: 258,501
Hi,

The Max DSLR adapter looks like a nice product, combining a T-Ring and a 2 inch EP adapter into one piece.

To me its one advantage is a wider aperture.

The web site states the "advantage" of being shorter than a standard T-ring adapter but you had to extend your refractor. I find my focuser is almost always extended almost as far as it goes.

The Web site also states it avoids having the T-Ring unscrew during operation. I find the real problem is the EP holder thumb screw slips. I prefer anything that screws on over a tiny set screw on a smooth surface!
Forum: Pentax DSLR Discussion 10-18-2010, 04:57 PM  
Weather Resistance? yeah how about coke resistance?
Posted By LeoTaylor
Replies: 9
Views: 3,578
I was going to say that! As a long time Diet Coke drinker (I started with Tab in 1966) I know the diet sodas don't leave a sugary residue.
Forum: Pentax DSLR Discussion 10-18-2010, 04:53 PM  
Spot histogram trick on Pentax cameras
Posted By LeoTaylor
Replies: 3
Views: 2,533
I use histograms occasionally, and the "blinking" overexposed areas often. I can't think of when I would use a histogram of only part of an image, I want to check the entire frame.

Perhaps this is because I usually have a Tamron 18-200 SuperZoom attached so can frame just what I will keep. If I had a short focal length prime then I could imagine keeping just a small area of the FOV.

I'll keep the trick in mind.
Forum: Pentax DSLR Discussion 10-15-2010, 05:58 PM  
After 4 Pentax DSLR, a first failure: Kx Died!
Posted By LeoTaylor
Replies: 13
Views: 3,509
I have five Pentax DSLRs and none have broken. They are not new models.

*stD
K100D * 2
K110D
K100D Super

Shutter counts via PhotoMe range from 3397 to 18859

Oh, I broke the K110D once taking the internal filter out and I paid Pentax to fix it.

Not one camera has failed on its own.
Forum: Pentax DSLR Discussion 09-29-2010, 11:09 AM  
Future K7 firmware updates?
Posted By LeoTaylor
Replies: 17
Views: 3,771
Then there is the matter of Pentax Remote Assistant for K100D, K110D, and K100D Super. A zillion requests from us owners to fix that and all were ignored. I do have an *istD which is supported by R.A. An unsupported K100D with version 1.0 firmware sort of works, but once upgraded it ceases to communicate.

I love my Pentax DSLRs but have little faith in software bugs being fixed.
Forum: Pentax DSLR Discussion 09-29-2010, 10:54 AM  
Astrophotography
Posted By LeoTaylor
Replies: 1,132
Views: 258,501
Here is another Pentax astrophoto, this time with a K100D Super I bought used on this forum's Marketplace.

Jupiter is the bright object on left, Uranus the dim one on the right. In September they were in opposition during the same week and less than one degree apart. It was the chance of a lifetime.

Jupiter's moons from top to bottom: Europa, Io, Ganymede, Calisto.

Taken 9/21/2010.

I had a problem with the wide dynamic range: MAG -2.7 in the same frame as
MAG 5.7 but was successful by letting Jupiter overexpose.

Meade 2080 SCT, f6.3 Reducer (think 1250 mm f 6.3 lens)
Ten exposures of 0.1 sec.
Forum: Pentax DSLR Discussion 09-25-2010, 07:51 PM  
Astrophotography
Posted By LeoTaylor
Replies: 1,132
Views: 258,501
It would be a long ride to visit a small Observatory. :p At 6 * 7 feet it will fit my 8 inch scope, one visitor, myself, not much else.

I would be delighted to show you some objects through a telescope, but I rarely, "look through" my telescopes except at public outreach events. Once you have taken astrophotos you can't go back. The following Lagoon Nebula (taken with a K110D) looks faint and gray when I use an eyepiece. I'm spoiled!
Forum: Pentax DSLR Discussion 09-14-2010, 07:43 PM  
Astrophotography
Posted By LeoTaylor
Replies: 1,132
Views: 258,501
OK, it is time for me to jump in. I've been doing astrophotography for many years including Pentax DSLRs.

"Jon in SC" received some good advice in his seminar in my opinion. Some things were lost in translation, I'll smooth the edges.

> From what he said any good DSLR without any adaptations can take reasonable shots of the moon or star fields or even star circles.

Yes, you can do astro without an expensive motorized mount. My wife took many Moon shots at using a $199 Orion 400 mm f5 telescope as a lens with a Bogan Tripod. She kept her Moon exposures under 5 seconds at 400mm. Any longer and the craters smeared. The same could be done with a 300-400 mm lens. The Moon will move and the tripod will need to be re-centered between shots. Focus is ALWAYS hard with astro, so take a lot of shots and hope to get a good one.

Star fields are doable with a wide lens. Wide field can expose longer before the stars smear. You can take multiple frames and stack them. I don't know what a Star Circle is!

> use as wide open F stop as you can (stop down to a crisp focus)

Using one or two stops short of wide open is good advice. Most lenses look worse wide open then a average telescope which does not have aperture control.

> He said that planetary images and more complex star images were also possible with any good DSLR if you attach an adapter mount and use a telescope that tracks with the sky.

To get any detail on planets you need a lot of focal length. I use 6000mm and at that FL you need a good motorized mount. But, I use a cheap web camera. The reason is you want to stack hundreds of frames and that is torture on a shutter based camera. Any camera that can do video with the shutter kept open can take hundreds of frames without wear and tear.

> It had something to do with de-activating or hyper activating the infrared sensor capabilities of the camera.

Daytime cameras have an IR filter to prevent excess IR from overwhelming the visible red. It is a lousy filter which also cuts off visible deep red which happens to be the color of many nebulas. So you can remove the filter (I did on my K110D) or replace it with an expensive filter that cuts IR but keeps deep red. My filterless K110D does pretty well on nebulas. If you don't plan on imaging nebulas then don't worry about the internal filter.

> He further said that Canon was the best camera brand to purchase for a camera to convert to this purpose.

Canons are the most popular DSLRs for astro, but not because they are easy to convert. There is more support for Canons but at least one vendor that will change filters in a Pentax.

> I quickly realized that I was unwilling to spend that kind of money to buy and convert a camera into something that could only be used for space photography

Everyone seems to think astrophotgraphy is expensive! I bought my K110D new for $349, used they must be dirt cheap. I bought that model since it does not move the sensor like my K100D making filter removing easier. Besides, my filterless K110D doubles as a super daytime IR camera. Exposures with a Hoya 72 are 100 times faster!

I presume the seminar mentioned dark frames. To get the noise out of long exposures you need to subtract dark frames. You can use the camera's NR but that takes away 50% of your evening. If your camera allows you to turn of NR than you can take a few dark frames after the imaging session and use software to subtract them. Most Pentax CMOS cameras do not allow you to turn off the long exposure NR, another reason to buy a used camera for astro!

BTW: I'm imaging now out in my observatory, but I went back to using an SBIG Astro camera after 3 years with DSLRs.
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