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From a photographer's perspective as someone that has never visited Big Lake, I expect the best afternoon overall perspective of the lake I've never seen web images of is from atop the northeast end of topo dome 8175 southwest of the lake towards the northeast. Reach the top via friction slabs due south.
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About 6pm>7pm PDT on a day with a deep blue sky, that ought to capture a superb image of both the lake and granite landscapes with an optimal amount of terrain detail shading. Too late in the day, the lake waters won't be a wonderful blue. Of course the reason there are no web photos is because people don't consider aesthetic perspectives and instead tend to just shoot from wherever they are at destinations that for Big Lake would be in the forested northeast section because that is where backpackers first reach the lake from Pingree and then plunk down where they notice others have been tenting. Google Earth GE, BigLake1.jpg.
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Another good late afternoon perspective closer to the lake is just below the above perspective and allows capturing the whole backdrop of slabs plus islands. BigLake2.jpg
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And another is at the end of the northeast peninsula due north across its more sheltered bay, directly in front of the main slab zone. That perspective might work best late afternoon in order to better capture closer shading surface perspectives though with just a token section of the lake. Well ideally if during rare calm after a pm thunderstorm has passed leaving blue skies and somewhat wet, more saturated with color granite surfaces. BigLake4.jpg
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On calm early mornings, areas mid right on the eastern shore may afford best views westward in best light because the canyon from the outlet west is rather low affording various sky reflection views with neat lake rock islands at mid frame. BigLake3.jpg
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And another interesting morning day hike about 8am with some minor route finding and a minor climb would be at 8040+ on the ridge east of Yellowhammer Lake that would provide nice wide panoramic image both YL and BL.
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As for the OP's question of potential camp locations with expanses for many tents, I'll suggest the gruss benches east of the lake north of topo point 7809 that also has many nice erratics about and a smattering of trees for mid day shade. Would be easy thereabouts to space tents for privacy too instead of having to listen to worst snorers haha. The nearest Big Lake shore areas from the "g" in gruss text is 200 yards away. Due to the way granite sand flats form within bedrock granite during heaviest t-storm event erosion, one can generally assume such substrates will be quite level and clean. Thus if one can identify such pre-trips on GE, affords a way to find out of the way camp zones instead of the usual well used lake and near trail camps.
Another benefit of that location versus the usually stale water due to its tiny basin inflows, is the stream out of Yellowhammer that undoubtedly has cleaner drinking water is just a similar distance south across an easy saddle. For other water needs like pan cleaning, the 3 frog ponds are nearby. And obviously Yellowhammer Lake with its cooler, more aerated water from a much larger basin supports a better trout population, something Big Lake has always lacked. Of course, the majority of visitors probably set up camps as close as they can get to lake shores that is not my own style and a reason no one on this board has probably ever camped there. So yeah, more privacy also on the Gruss Benches. BigLake-camp.jpg
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