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Forum: Pentax DSLR Discussion 7 Hours Ago  
Battery Shelf Life
Posted By DeadJohn
Replies: 16
Views: 531
I think you've lost track of the original poster. The OP just received a battery that was manufactured at the end of 2018.

The batteries from 2012 were purchased by others, and received a long time ago. They've been using the batteries for years through many recharge cycles.
Forum: Pentax SLR Lens Discussion 2 Days Ago  
Need advice on Lens what to chose
Posted By DeadJohn
Replies: 22
Views: 594
Pentax DFA 28-105 has good optical performance: sharp, good contrast, and decent flare resistance when sun is in frame. The compact size and light weight are good for long hikes.
Forum: Pentax SLR Lens Discussion 08-15-2021, 05:42 PM  
Moon with Two Old(er) Lenses
Posted By DeadJohn
Replies: 13
Views: 772
Sorry for hijacking the thread replying to someone else's photo, but my comments on settings are relevant to any lens.

Your picture shows more color fringing than I expect from the 150-450. Being out of focus can increase fringing, so maybe it's just a case of slightly missed focus rather than a lens issue.

Shutter speed also seems slow at 1/30s. Assuming your EXIF data is correct, try ISO 400 instead of 100, and then increase shutter to 1/120.
Forum: Ricoh GR 07-30-2021, 03:23 PM  
any tips for street with gr iii?
Posted By DeadJohn
Replies: 14
Views: 1,807
"how to overcome my intimidation". It's a matter of your own comfort and self-confidence. There's no answer that works for all photographers. Here's what worked for me:
  • Doing more street photography can help increase your comfort level. Parades and other celebrations are a good starting spot because no one is expecting privacy and everyone's in a good mood.

  • Avoid taking photos that demean people, such as identifiable photos of people who seem homeless or in some sort of crisis. You'll be more confident when you don't feel guilty.

  • Think about what you will do if/when confronted by someone. Will you immediately delete photos? Will you assert your right to take photos in public? (There are 3 versions of the "someone": truly crazy people, people with an overactive sense of privacy, and security/police).

Getting close: I shoot from the hip, often while I am walking somewhere. I'll start with TAv mode, 1/400 shutter, f/8 for depth of field, then adjust depending on available light and how quickly I and others are moving. Set manual focus at 2 meters and leave it there. I can snap mid-gait as subjects approach me. I crop for composition later because it's easy to tilt the camera or get clutter in the scene. Example #1 below.

Wider scenes: This allows more careful attention to composition. I look for a high foot traffic spot with interesting light, color, or architecture. Wait for people to walk through the scene. #2 below.

20150529-R0001196.jpg by jvsperoni, on Flickr

20160922-R0003371-Edit.jpg by jvsperoni, on Flickr
Forum: Troubleshooting and Beginner Help 07-23-2021, 09:12 PM  
Image not sharp what am I doing wrong??
Posted By DeadJohn
Replies: 30
Views: 1,475
Long focal lengths magnify everything in the scene, including any atmospheric effects. Wind, humidity, thermal currents, etc. can distort extreme telephoto targets. When you look at a bright star at night on the horizon, and it twinkles, similar atmospheric effects are involved.

As already mentioned, f/14 reduces sharpness a bit. f/8 is a good default setting for many lenses when you want sharpness and some depth of field.

Here's a similar scene of mine. Notice how the flagpole or antenna on the left side is wavy, and there are notches in the sun's edge.

Fire Island Lighthouse by jvsperoni, on Flickr
Forum: Pentax DSLR Discussion 07-20-2021, 10:07 AM  
What are your top 3 bucket list destinatons?
Posted By DeadJohn
Replies: 43
Views: 1,468
I'm going to list 4:

Alaska and Canada RV trip, with ferry from Seattle to Alaska, then drive home through Canada.
Forum: General Photography 07-20-2021, 09:20 AM  
New 16-50 f2.8 vs 15-30 f2.8 for landscapes and Astrophotography on K1
Posted By DeadJohn
Replies: 12
Views: 677
The new (and old) 16-50 is not a good match for the K-1. The lens is designed for APS-C crop sensor, not full frame. You'll get heavy vignetting (outer edge of your photos will be too dark, and the corners are likely to be completely black).

The 15-30 is a good choice for wide angle astrophotography of the Milky Way and star trails. It's also good for landscapes, although ultrawide can be challenging for many scenes. Image #1 and #2 below are at the extreme wide end. (note that #2 was a hazy night which didn't give me quite the result I envisioned, but I haven't had a chance to revisit). My only complaints about the 15-30 are that it's heavy, bulky, and needs an awkward filter arrangement.

The 28-105 is by far my favorite landscape lens. Excellent image quality, very versatile zoom range, compact size allows inexpensive filters. It also works for astro scenes with the moon plus foreground elements, and should work fine for star trails but less so for the Milky Way because it's not f2.8 or faster. Image #3 and #4 are with the 28-105. I have zero complaints about the 28-105.

My suggestion: practice with your existing 20mm lens for landscapes and astro. If it's not wide enough or has poor image quality, buy the 15-30. If you can get by with the 20mm for now, then consider spending your money on the 28-105 for landscapes.

Milky Way and Andromeda through Trees by John Speroni, on Flickr

Pemaquid Point Milky Way and Mars by John Speroni, on Flickr

20210407-IMGP2538.jpg by John Speroni, on Flickr

Andromeda Galaxy above Thunderstorms by John Speroni, on Flickr
Forum: Pentax SLR Lens Discussion 07-16-2021, 11:36 AM  
To hood or not to hood?
Posted By DeadJohn
Replies: 73
Views: 2,055
Hood almost all the time. Main reason is that the hood cuts down on glare, improving contrast. It also protects the front element from dirt and scratches.
Forum: Pentax SLR Lens Discussion 07-12-2021, 10:52 PM  
Best Weather Proof/ Weather Resistant lens for videos of firefighter trainings
Posted By DeadJohn
Replies: 30
Views: 1,071
I'll add to those who already said a gopro or similar sealed camera. Heavy smoke and high pressure water from hoses exceeds what "weather-sealing" is supposed to do.

Maybe go with something like this up close Video Cameras and Accessories, and then a normal camera at distance.

Since you're a cadet, ask your instructor for permission to contact whoever runs the burn building. They've probably done video in there before so ask what they've used.
Forum: General Photography 06-19-2021, 01:09 PM  
Dumb features on cameras
Posted By DeadJohn
Replies: 80
Views: 3,303
With respect to Pentax products, one of the dumbest design oversights I recall is the bright blue power indicator light on the O-GPS astrotracer. It should have been much dimmer (and red or amber) for the intended night usage.

The 35mm equivalent is helpful for people who own multiple cameras with different sensor sizes.
Forum: General Photography 06-19-2021, 12:37 PM  
Love or loathe camera clubs/societies?
Posted By DeadJohn
Replies: 64
Views: 2,389
I tried a weekly local camera club for a few months. It didn't work well for me. I don't "loathe" them but I'll wait a few years before trying again.
  • Roughly 33% of meetings were competition. This was all about grading by some guest judge with minimal feedback. My main motive to share photos is to foster discussion, not to earn points. I like dialogue about what other photographers may have done differently with respect to composition, settings, or processing; that rarely happened.

  • In order to become a full participating member, I needed to go through an ill-defined process with a "mentor" who always seemed too busy to communicate with me.

  • I was helping other clubs with astrophotography classes. Those clubs were too far away for me to regularly attend. The local club, though, seemed uninterested in astrophotography.

  • The Sunday morning photo gathering was unwelcoming to new members.

Forum: General Photography 06-15-2021, 08:21 PM  
Heat affect on my k-3 and k-5
Posted By DeadJohn
Replies: 10
Views: 419
Don't leave the camera in an unattended vehicle. Take the camera with you when you leave the vehicle; that protects against heat and theft (someone's less likely to mug you than to break into your car). When you are in the car the A/C will be on or you'll have the windows down.

If you absolutely have to leave the camera in the car for some reason, leave all the windows open a little, and keep the camera on the floor out of direct sun.

A cooler can offer a thermal barrier that heats up slower, but I don't recommend ice packs because you'll stress the camera moving from very cold to very hot. Heat's not great for the camera but extreme temperature swings are bad, too.

111F is hot but the camera should still work okay and not be damaged. You will get more noise at high ISO. Avoid very long exposures.
Forum: Pentax SLR Lens Discussion 06-09-2021, 07:17 AM  
Lens for shooting Northern Lights with K-70
Posted By DeadJohn
Replies: 22
Views: 1,333
Good question about decentering. I think it's just a case of fewer bright stars on the right side, so you notice less coma there, rather than a decentering issue.

Here's another example where a very good general-use lens, my FA 43 f1.9, comes up short for astrophotography. It's my fastest lens but has horrible coma. This sample was with the crop K-5 and would be even worse with full frame. It's interesting how the coma pyramids point towards center with the FA 43, and away from center with the earlier DA 14 example.

20131001-IMGP4391.jpg by John Speroni, on Flickr
Forum: Pentax SLR Lens Discussion 06-08-2021, 10:27 PM  
Lens for shooting Northern Lights with K-70
Posted By DeadJohn
Replies: 22
Views: 1,333
The Pentax DA 14 has much more coma distortion than the Samyang 14. This photo below is not mine; it was put online by a Pentax 14 owner. Look at the bright star near the top-left corner; the star has been distorted into a triangular fan shape. That's coma distortion. Lesser amounts of coma are visible on many other stars. Coma is not something that's easily correctable with technique or processing. (click for the original photo on Flickr)

For anyone who already owns a wide angle lens, I suggest testing your lens for night photography. Any lens is good enough to learn on. Maybe the lens you have is an especially good copy. But if you are interested in getting a lens specifically for wide angle night sky photos, the Samyang/Rokinon/Bower 14/f2.8 is a good choice and much less expensive than the Pentax 11-18 or 15-30.

Cyprus Astro by Robert Seymour, on Flickr
Forum: Pentax SLR Lens Discussion 06-08-2021, 03:11 PM  
Lens for shooting Northern Lights with K-70
Posted By DeadJohn
Replies: 22
Views: 1,333
I recommend something fast and wide for aurora, milky way, and star trails.

The Samyang 14mm f2.8 is IMO your best choice:
  • It is sharp at f2.8. There's no need to stop down and lose light to get sharp stars.

  • It has a very low amount of coma distortion. "Coma", if you're unfamiliar with that term, causes stars to become stretched ovals or fan-shaped at the edges of the frame. Coma is usually invisible during regular daylight photos and few lens reviews test for it.

  • Samyang is manual-focus only, but that's the best way to focus on the night sky, anyway.

  • Note that the same lens is also sold under the names Rokinon and Bower. All three of those 14/2.8 lenses are the same design so get whatever is least expensive. (Pentax also has a 14/2.8 but that's a completely different lens not as good for astrophotography)

Forum: Pentax SLR Lens Discussion 06-01-2021, 09:01 PM  
AF full-frame ultrawide lens that takes threaded filters ?
Posted By DeadJohn
Replies: 51
Views: 2,130
Isn't that lens designed for an APS-C size sensor? The thread title is asking for full-frame and I think a 17-50 will have severe vignetting.
Forum: Photographic Technique 05-30-2021, 05:50 PM  
Astro Need advice: Star Trails and Milky Way Wide Field Planned First Attempts
Posted By DeadJohn
Replies: 26
Views: 1,863
20 seconds is if you want foreground plus untrailed stars in same shot. You are correct that astrotracer can go much longer, but then the foreground blurs which adds processing complexities.

Liveview zoom is what I use most of the time. Bahtinov mask is IMO not for wide angle; it's more of a tool for 300mm+.

Longer exposures are usually better (less noisy, fewer frame to process) for both Milky Way and star trails. The longer you go, though, increases the risk of unwanted star trailing for the Milky Way. Even with star trails it's possible to go too long if the sky background causes overexposure but that's more of a problem when there's light pollution.

Dark frames aren't needed for star trails since you'll be stacking. They don't hurt, but remember that dark frames need to be taken near the same temperature as the photos, so it's best to take them after your light frames when the camera has warmed up. Simple noise reduction software, without dark frames, is IMO adequate to deal with hot pixels.
Forum: Photographic Technique 05-30-2021, 01:43 PM  
Astro Need advice: Star Trails and Milky Way Wide Field Planned First Attempts
Posted By DeadJohn
Replies: 26
Views: 1,863
Star trails are much more forgiving exposure-wise than the Milky Way.

Milky Way tips:
  • Don't worry too much about EV. I suggest starting the night with an educated guess at exposure, then take a test shot and examine it to see if you need to adjust settings.
    • At 24mm f2.8, I would use 3200 ISO, 20 second shutter for my first test shot. (although anywhere from 1600 to 6400 ISO can give similar results; lower ISO gives less initial noise, but you'll need to lift shadows more which adds that noise back in)

    • Zoom all the way in to the test shot to check focus, star trailing, and tripod vibration. A little bit of trailing is okay; you won't notice it at normal viewing sizes.

    • Check the histogram. Make sure it's not too far to the left with completely clipped blacks. A histogram peak approx. 1/3 of the way from the left is a common suggestion.

  • I suggest not stacking/stitching your first Milky Way shots. You already have enough to learn with composition and exposure.

  • The brightest portion of the Milky Way from the northern hemisphere is to the south, in the direction of the constellation Sagittarius. Compositions to the north can still work, but try a shot to the south for comparison.

  • Check moon phase in advance. On moonless nights, feature the Milky Way. On moonlit nights, get an interesting ground feature lit up, and expect the Milky Way to be washed out.

Star trails are IMO more forgiving than the Milky Way.
  • You asked whether 1 minute exposures are okay. Yes, they are. 30 seconds is a more common recommendation I think just because that's frequently the longest exposure allowed on some camera models.

  • If you have 2 hours to do star trails, I suggest 2 different 1-hour compositions, in different directions and with different landscape elements.

  • Make sure to use settings that minimize gaps between exposures. While the 2-second timer is great for the Milky Way to reduce vibration, don't use that if it will give you a 2-second gap in every star trail frame.

  • The free software StarStax is one of the easiest ways to combine exposures. There are many other ways to do it, though, including in-camera, other free software, or Photoshop layering.

  • I prefer to not use in-camera stacking for star trails. Software stacking gives you more flexibility, and you can reprocess old photos as you get better with processing. For example, if you have unwanted aircraft light trails in your star trail stack, you can do a simple processing and leave them in for now, then learn how to erase the aircraft later.

Forum: Pentax DSLR Discussion 05-30-2021, 07:50 AM  
Drop-in (clip-in) filters by STC - user experience?
Posted By DeadJohn
Replies: 9
Views: 747
I think it's reasonable to assume STC tested lenses based on Pentax' stated frame sizes(*): full frame lenses get tested on a K-1, APS-C lenses on an APS-C body. You would need to ask STC to confirm, though, since my message to them was focused on the K-1 15-30 and K-1.

(*) There are some lenses that are in the APS-C "DA" series but ever since the K-1 came out have been commonly considered full frame compatible. Depending on how well STC knows Pentax, they may have tested those as either APS-C or full frame.
Forum: Pentax DSLR Discussion 05-29-2021, 01:51 PM  
Drop-in (clip-in) filters by STC - user experience?
Posted By DeadJohn
Replies: 9
Views: 747
The STC rear mount clip-in filter is unfortunately not a solution for the 15-30.

I was interested in their astrophotography clip-ins. The 15-30 was not in the list of compatible lenses, and I was curious whether there was a known problem or maybe the lens just wasn't tested yet. STC replied that there's vignetting when that lens is used with their clip-in filter.
Forum: Pentax K-1 & K-1 II 05-29-2021, 12:44 PM  
15 limited on the k1
Posted By DeadJohn
Replies: 20
Views: 1,678
Is your signature current? It looks like your current camera is K-70 and you haven't bought the K-1 yet.

If you are getting the K-1 mostly for wide angle starbursts, reconsider because you'll need to crop so much that the K-1 will give results around the same as the K-70. The K-1 in 1:1 ratio, however, can give you more vertical resolution than the K-70.

Here's a non-cropped sample of K-1 and DA 15 so you can see how extreme the vignetting can be.

Pentax DA 15 by John Speroni, on Flickr
Forum: Pentax News and Rumors 05-28-2021, 02:15 PM  
Ricoh Developing OGPS2
Posted By DeadJohn
Replies: 112
Views: 8,091
Ugh. While the cooker might be able to function for more than a decade, the app will probably be unsupported long before that.
Forum: Pentax SLR Lens Discussion 05-25-2021, 12:12 PM  
A test of 4 ultrawides on a K-1
Posted By DeadJohn
Replies: 19
Views: 3,238
I haven't missed having filters with my 15-30. Ultrawide angles don't work very well with CPL filters, I can composite to simulate GND, and in some cases I can use multi-exposure to simulate long-exposure ND.

In cases where I do want to use a filter, I change to the 28-105 lens. The 28-105 plus a few round filters are small enough to keep in my camera bag with the 15-30.

There are square filter solutions for the 15-30 but they are awkwardly bulky. The Pentax 15-30 is a re-branded Tamron, so try searching for "Tamron 15-30 filter".
Forum: Pentax SLR Lens Discussion 05-24-2021, 06:50 PM  
A test of 4 ultrawides on a K-1
Posted By DeadJohn
Replies: 19
Views: 3,238
Sorry the lens didn't work for you. My test was indoors in dim light rather than the bright sky you tested with, and in hindsight my test may have missed some vignetting.

I never did get around to doing more extensive comparison testing. I committed to the Pentax 15-30 and sold my Samyang and Tamron.

I'll update the top post to tell people to scroll down to yours for more info.I guess I won't. My posts from 2017 (not just the top one) have no edit button.
Forum: General Photography 05-24-2021, 06:36 PM  
Lunar Eclipse coming up May 26th
Posted By DeadJohn
Replies: 17
Views: 980
I usually look for a bright star near the moon then recompose. Focus until the star is as small as you can get it. It's easier to judge focus with a pinpoint than it is to assess the lunar surface.
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