[SSGGeezer]

Red enhancing filters! Especially if near a built up area. Not the cheapest of filters but a 49mm for your DA 40XS and a Kood step up ring would be a good investment Allen.

[Auzzie-Phoenix]

Waaayyyyy too early to predict cloud cover. I know some areas are fairly reliable at times... but a month is still a ludicrous amt. of time. I don't trust the weather here for more than 72 hrs in advance, and even that's iffy.

[aslyfox]

Waaayyyyy too early to predict cloud cover. I know some areas are fairly reliable at times... but a month is still a ludicrous amt. of time. I don't trust the weather here for more than 72 hrs in advance, and even that's iffy.

you're correct but it's fun to look

[MossyRocks]

Red enhancing filters!

I appreciate this advice. I have been looking for a filter to deal with the sodium vapor light pollution and not knowing what to search for was looking at narrow band silly expensive astronomy filters. Now I have something that likely will get me basically what I need but not at stupid expensive prices. For some more info on these filters and how they perform for astrophotography read here.

[jatrax]

trust the weather here for more than 72 hrs in advance

72 hours! Wow. I usually figure 12 hours and that only has a 50% average. But I live on Mt. Hood and things can and do change in minutes, even when the weather report says full sun it can be raining at my house. Or the other way round.

I figure if I want to know what the weather is, I stick my head outside.

---------- Post added 04-18-18 at 09:45 AM ----------

Case in point. Weather called for a clear night last night. First in 10 days. Kept waking up every hour to see if I could go out and do some test shots. And it rained all night................

[aslyfox]

72 hours! Wow. I usually figure 12 hours and that only has a 50% average. But I live on Mt. Hood and things can and do change in minutes, even when the weather report says full sun it can be raining at my house. Or the other way round.

I figure if I want to know what the weather is, I stick my head outside.

---------- Post added 04-18-18 at 09:45 AM ----------

Case in point. Weather called for a clear night last night. First in 10 days. Kept waking up every hour to see if I could go out and do some test shots. And it rained all night................

to check whether it is raining, I trust my hat

the one with the sides made of open mesh

if my head is wet, it is raining ( I hope the moisture is rain )

[jatrax]

if my head is wet, it is raining ( I hope the moisture is rain )

Yeah. That's always a good hope.................

[AstroDave]

Gifthorse (nice pix!!) beat me to some of this!

For even more fun, and something that can be done even from fairly bright sky locations, try taking time-lapse shots of either the Space Station soaring overhead, or Iridium flares (Satellite flare - Wikipedia).

The Heavens-Above web site will give you the event timing:

Heavens-Above (for Yellowstone Park).

Click on either the ISS (International Space Station) or Iridium Flares options to see what will be visible in the next few days, from whatever location you have chosen.

Or for Yosemite Park: Heavens-Above

I’ve found the site does a good job of knowing your local time (probably gotten from your computer), but pay a bit of attention to the time tags. Then, all you need to know is how to point close to the elevation and azimuth of the satellite tracks.

This is not as simple as it sounds! Azimuth - the angle from north through east and on around - is quite straightforward as long as you know where north (or any other compass point) is, but most folks aren’t very good at estimating elevation! For example, ask somebody to “point straight up” (i.e. elevation 90 degrees) - they will point to about 70 degrees at most. If you are pointing straight up, your arm will be BEHIND your head - you almost can’t point that high!!

The Heavens-Above web site shows the expected brightness of a pass, in astronomers’ units of magnitude. The magnitude scale is such that brighter values are smaller, or even (more) negative. An ISS pass at magnitude -2 or -3 will be quite bright, and an Iridium flare of magnitude -6 to -8 can be quite spectacular.

Here are are a few Iridium flashes from my collection of such shots. Typical exposures are a couple of minutes at ISO 200 or 400 and f4 to f8.

Iridium Flare pair - these two occurred within a few minutes of each other in almost the same place in the sky (rather rare!!). The first was made with a Rebel Xti on a fixed mount, while the second was with a K-5 on a tracking mount. The difference in the mounts causes the slight difference in spacing between the two flashes.






Sometimes you get other interesting things in the FoV - like the two airplanes which passed by during this shot




This 5-minute exposure was made during almost full moon and looks like a daylight exposure, despite the star trails and flare

[aslyfox]

well I am off to Yellowstone Monday but according to the forecasts I only have 2 days of " fair for star gazing " towards the end of my trip

https://www.accuweather.com/en/us/yellowstone-national-park-wy/82190/astrono...0138_poi?day=8

I am easily confused so I don't understand why it is forecast for " fair " with cloud cover of 84 % predicted for one of the days??

at least I know I won't have an opportunity for any moon photos as it is the new moon.

and if I understand it, the " Milky Way " won't begin to rise on the southern horizon until midnight or later on those days


any thoughts or suggestions?

[dsingley100]

New to astrophotography. Have the good fortune to be spending a few days, during the new moon, in a dark sky area. Shooting a K-70 w/ the 16-85 lens. Also have the Pentax GPS unit. Question is exposure settings. No GPS, I’m looking at a max shutter speed of 21 seconds. I figure I’ll have to fiddle the ISO to get an image -likely something in the 6400 range. Any noise experience thoughts at that high an ISO on the K-70 would be appreciated. So with the GPS, what kind of a max shutter speed am I looking at? My working assumption is that there is an upper limit, but have not seen anything on that point. Not worried about stopping down, but am thinking I’d like to bring the ISO down to the 1600 range or lower if possible.

Appreciate the help. Thanks.

D.

[dsingley100]

Very new to astrophotography. Am going to be in a location with dark sky access during the new moon. Shooting a K-70, with the 16 to 85 lens. Also have the Pentax GPS unit.

Question is as to settings, particularly with the GPS and astrotracker engaged. I assume there is some upper limit to exposure time when using the astrotacker/GPS. Anyone have any idea what it is, or what exposure lengths have been made without star tracks (and at focal lengths and/ISOs). At the risk of stating the obvious, I'll be at the widest aperture and likely ISO 3200 or so. If i could bring down the ISO, I'd like to do that. I'm likely going to be down in the 16 mm range for focal length.

Appreciate the help and insight.

[Kevin B123]

Appreciate the help and insight.

You might fine these pages absorbing for a while
Astrophotography - PentaxForums.com
Astrophotography Series Announcement - Articles and Tips | PentaxForums.com

[AstroDave]

I'll be at the widest aperture and likely ISO 3200 or so. If i could bring down the ISO, I'd like to do that. I'm likely going to be down in the 16 mm range for focal length.

I would start out with ISO more like 400-800 . For even 30 second to 1 minute exposures, the sky background (especially if there is any moon up), will start to be apparent. A few exposures without tracking at different ISOs and apertures will give you good ball park values as to what to use for your "real" exposures.

[dsingley100]

Thank you for the replies. I do anticipate some guess work and hearing ISO 800 is good news. IMHO K-70 is solid at ISO 800. All I need now is some clear sky😀.

ps Apologies for the duplicate post. Did not realize the first one went through.