Was there in August and captured several shots from different perspectives, I like how yours has been composed, nice job.

Congrat's NoSocks, I was fortunate enough to have one of my images displayed in a calendar this year, I equated that as free advertising and they gave me 15 calendars which I was able to give to folks, no money was asked for nor offered. As far as what monetary value this provides is likely debatable so what is a photograph worth. All photos cost us something so any return on the investment (camera, time, lessons learned, training, cost of storage, equipment, post processing, etc) should be recouped.

I basically did the same as you did, when I think of that today what did it gain me to just hand that photo over, I haven't been asked by anyone from that calandar shot to come on over and shoot this thing for money. If I had asked for a few cents for each copy distributed I may have received a couple thousand dollars, it's a tough question to answer, how much should I ask for and a good question for discussion on this site. I don't have an answer but I bet someone here has experience with this type of scenario. No one has however stepped up to help with your main question of 'What is the monetary value - I'd like to know the answer as well.

I have the Nikkor 70-300mm VR f/4.5-5.6 which I shoot with my D750. Yes it is heavy however it does work well, have hand held and captured some good clear images, the trick is to make sure your very stable because any movement as you likely know will kill a shot. I have hiked with it around Yellowstone carrying it attached and around my neck, it can get heavy and awkward, I just make sure I keep one hand on the camera to make sure nothing swings away from my body. The best method is to use a tripod, the lens does not have a mounting bracket for the tripod (been considering looking for one) so even with a good ball head the weight tends to let the lens drift down from your original composition, I just compose a little high in the beginning. All in all, good lens, quality glass, durable, easy to zoom and smother focus. Hope this helps your quest, I would recommend the VR however.

I did export while on the road, I actually used my personal hotspot on my phone, couldn't use the provided weak wifi. It worked however slow and it used significant data.

Came with my D750 in the kit, 24-120mm f/4, works great for hand holding or tripod, I tend to use it a lot lately it gives me the ability to be quick when needed. Darker conditions are difficult without a tripod unless you increase the ISO on the camera, I try and keep it at 100 or 200. I have shot inside with a flash at 400 up to 800 with good quality. As far as landscape, seascape, general event and portrait type shooting it provides good quality with crisp details so I would recommend it, I am however in the market to find a 1.8 or 2.4 so I can get better dark time shots. Hope that helps in your decision process.

I always take 2 cameras, my backup is set for auto modes, don't use it often in that manner however allows me to capture a quick image like the one you apparently missed. I've had the same situation occur that's why I now carry the second camera set to auto even on manual ISO, typically set at 200. When I have time to reset the alternate camera to manual it is accomplished quite easily, besides all of that my wife can shoot in auto while I shoot in manual, sometimes she gets some great shots that I can pp and no one will ever know it was shot in auto - everything is however shot in RAW.

I own the D750, it is a great camera and I would recommend it. Been shooting Nikon for several years and am used to the functions, the 750 is easy to focus, shoots any time of day and is very complex with so many controls, I keep the manual close for reference because every shoot can utilize different techniques that this camera can accomadate.

I utilize the 24/120 for both carry around and tripod, light enough for carrying in town or a hike, clear photos day or night, have shot in low light high ISO situations with very sufficient quality hand held. I also carry a 70/300 4.5 Nikkor, another great lens, best for tripod usage however have also shot using hand held, great quality. Have also utilized older lenses I have with crop factor, it can fool you however it will take ok images you just need to remember to see the photo through the bracketing in the viewfinder and remind yourself it's not full frame. Depending on what you shoot you may want a lense with a 2.8 or lower but you will pay for that capability, I'm still searching for a good deal there.

All in all, The D750 is a fun camera to own and full frame is the way to go.

Easiest way that I have found is to sequence normal, under, over, after the sequence place your hand over the lense hood before and after your sequence and snap a shot. This separates your bracketed shots from singular then after you've downloaded from your card you can see in LR, Bridge, PS or any other program the separation of your bracketed sets.

I post to get a sense if my image and post processing will be good enough to enter a contest for the most part. On the other hand I will post into a contest or a sharing site to get a feel of what others may think is a good image.

I too like a pat on the back when an image is well accepted, this helps to build my portfolio of images that I can keep on my website. The idea behind this is that it could generate income at a later date, I'm retired so what the heck any additional income I generate can fill the photography itch that I have.

I've never posted here, maybe some day I will. Rongnongno hit the nail on the head for many sites, those I try the fleet foot out of, they just get to be a waiste of time, energy and resources. I do however participate on sites ( I pay a yearly fee for) because I tend to get a respectful response good or bad but people are very thought provoking in their feedback.

So, I'm sure I'll get the usual positive and negative responses from this post. I regularly read here but seldomly post replies however this particular subject was one that caught my attention.

Personally I'd stay away from a Windows machine and go with a MAC. I use both and the MAC performs much better. I've processed in both LR and PS on both and always redoing the work on the MAC that I previously did on Windows due to the resolution of the screen. You'll spend a bit more for the MAC however, your overall quality will be greatly improved. Depending if you use a separate hard drive unit for your photos I would think a MacBook Pro 15 inch 16 GB Ram with the 524 GB storage should work fine, you'd need to double the Ram with a Windows product. The MAC would set you back about $2,600 from PowerMax out of Oregon with no sales tax. Just some thoughts to help your decision.

When using the lens on your D750 you should see the reduced size in your viewfinder, I have a lens that does the same thing. You'll notice the boxed crop when taking the photograph, just a little more info so your not suprised like I was the first time I used the FX on my 750.

Answer to a couple of your questions:
Do you need a 4X4 - likely not for Yellowstone however if you are staying outside of Yellowstone you have to answer the question 'where am I interested in going' there is a lot of country to explore if you have the time and are eager enough.
Taking a tour - if you like to travel to the villages and shop with the masses go for it, if you are more of a free spirit adventurer take the rented vehicle, visit certain quadrants of Yellowstone each day, you'll need likely 5 days to fully see all it has to offer, each entrance has different aspects of the wilderness.
One other piece of advise if you don't like crowds then mid September beginning of October are good times, if you like crowds do the summer July and August. Have some fun.

I'm going to do the same thing at an upcoming wedding, I figured that I would do alternate location from the paid photog, mine will be for free sharing with family and I'll likely use some for contests and what not. Therefore, I wouldn't say rude because lots of people take photographs at weddings and I figure mine will likely be as good or better than the paid photog, illegal, not, public locations are open to all that care to photograph and I have already asked the bride and groom if they minded if I shoot their wedding. All just my point of view but who am I.......

Checked mine and fortunately is not affected. Good thing because I'm a week away from a photo journey through Montana, Wyoming and parts of Colorado, lucky me!

Here is one I shot from my deck on the 4th